GAY HAINES - Former chairman and chief executive, Kendall Tarrant
When, in 1996, it was mooted by an adviser that we take Kendall Tarrant public and float it on AIM, I am afraid I let vanity get in the way of good sense.
The notion of me becoming the chairman and chief executive of a public company was all too much. For a while, the shares did spectacularly well, because all shares were doing spectacularly well. But when the recession of 2001 hit us, I had just opened the offices in New York and Hong Kong and was in the process of launching San Francisco and Sydney. It was a disaster; my timing simply could not have been worse. No sleep for many months.
In the end, did I learn a lot? Yes. Would I do it again? No. For me, it was just too expensive, too hard and my failings were just too public. Only when I hired my replacement, Angela Campbell-Noe, did I realise how that job should be done. For, while I am a half-decent headhunter, a great public company chief executive I am not.
ROBIN WIGHT - Founding partner, WCRS
"The man who makes no mistakes, generally makes nothing," was the dictum of the US lawyer Edwin Phelps.
Many years ago, I told this to my then financial director. He swiftly replied: "On that basis, Robin, you'll do very well in life."
I've certainly made the mistakes.
Highlights, if that is the right word, of the low points would probably including the 2002 campaign we did for the National Lottery to launch Lotto. Apart from being voted the most irritating ad in 2002, it even made the front cover of Private Eye: "Don't annoy viewers a little with your ads ... annoy them a Lotto."
The problem here was to tie Billy Connolly to a script rather than to let him ad lib, as he did on his shows. As a result, we made Britain's funniest man unpopular, an achievement that undoubtedly played a role in our losing the National Lottery account.
There was an even bigger business mistake in 1991, though. This was when Havas obtained control of WCRS and its worldwide network. I remember my founding partner Peter Scott telling me he could help organise a management buyout of the London agency. At the time, an attempt to rebrand the agency as WCRS Matthew Marcantonio had just failed and there wasn't much management I wanted to manage a buyout with. But once Andrew Robertson (15 years later the chief executive of BBDO) was installed, WCRS leapt forward.
But only as an advertising agency: Havas didn't want us to do more than that.
Had we owned ourselves, I'm sure that we would have invented Engine - the group that now includes WCRS and seven other communication businesses - 15 years earlier.
But at least it was a mistake that I learnt from: 15 years later Engine is now a bonny one-year-old.
CHRISTINE WALKER - Chairman, Walker Media
Sir Martin Sorrell thinks that one of my mistakes was not joining WPP; Lord Saatchi doesn't agree. My real mistake was not starting Walker Media a decade before I did. That, and the name-dropping.
One recurring mistake I make is an inability to say no. Pathetically, I always fall for the flattery and end up merely adding to my work schedule. Another recurring mistake is to go out on the town too often, smoke too many cigarettes and down too many glasses of wine. I've never learned the art of self-preservation.
But the mistake I'm most ashamed of relates to the Britvic company. In the early days of Walker Media, the company invited us to pitch for its media account. We put our heart (actually, too much heart) and soul into it. The decision-making process dragged on and on and, by the time we learned we hadn't won, I was ready to be admitted to The Priory. Rather than accepting rejection gracefully and professionally, I laid into a senior Britvic executive and told him how unprofessional their pitch process was, etc, etc. Not smart, and very rude, of me. Andrew Marsden, the category director at Britvic, has graciously kept this "our secret" for years ... And now it's out.
I don't like being confessional, and this is the first and last time I will be.
JOHN HEGARTY - Chairman and worldwide creative director, Bartle Bogle Hegarty
This certainly wasn't my biggest mistake, but it certainly was my most memorable.
It was in 1989, or thereabouts, and I had been working with Paul McCartney on the publicity of his album Press to Play.
He'd asked me to write up some ideas for a music video for one of the tracks that Bob Giraldi, the American director, was going to shoot.
I had met Giraldi and showed him some ideas, which he seemed pleased with. I then went off to Sussex to present them to McCartney. He was then plain "Paul".
Sadly for me, he liked none of them and suggested I come back on the Monday with some more ideas.
As this was Friday afternoon, I pointed out that didn't give me much time. And anyway, I implied, with a certain creative haughtiness, "nothing great happens in a hurry".
"Oh yes they do," he said. "I wrote Yesterday in three minutes."
If only I'd retorted: "But imagine, if you'd taken four, how much more successful you'd have been."
The music video? In the end, he went with an idea he had.
SIMON CLEMMOW - Planner partner, Clemmow Hornby Inge
I could tell you about the time I forgot to pour the gin-and-tonics at 5.30pm as a planning trainee and department dogsbody; I could tell you about the time I had to brief Dave Trott on a new campaign only to find he was a better planner than I was; I could tell you about the time we nearly went bankrupt at the height of our success at Simons Palmer; I could tell you about the time we signed a long-term, punitive lease on our building with no break clause and rent reviews upwards only; I could tell you about the time I thought being on the worldwide board was important and would make a difference; I could tell you about the time I got fed up with a prospective client interrupting my pitch presentation and suggested we call it a day rather than carry on.
But I'm not going to tell you about any of those things. Instead, I'm going to leave you with a bastardisation of a 1973 Paul Simon lyric: "When I think back on all the mistakes I made in advertising, it's a wonder I'm still here at all." I think that says it all.
JONATHAN STEAD - Chief executive, Rapier
Many, many mistakes, small and big. In the early days of running my own agency, I managed to leave my notebook in my financial director's office. Point three on my "things to do" list being "get new finance director". One of those howlers that still makes me go into a Tourettes-like spasm on recollection.
One rather large one was launching wholeheartedly into the "integration" thing too early. At the time, I thought it was fundamentally "doing the right thing" by our clients. But after spending huge amounts of time and money on re-engineering Rapier, I realise we'd shot our bolt too early - about ten years too early. There weren't enough people buying it at the time. Fingers crossed, it was a timing error, not a stupid idea.
JON CLAYDON - Chairman, Zulu
Mistakes are under-rated and I should know because I've made quite a few. This is probably why I've now persuaded myself that they usually end up being a good thing; first, because they're often the only time when smartypants chief executives actually learn their lessons and second because you mostly make them when you're trying to change things. The definition of insanity in our business - and you see it a lot - is when agencies do the same thing over and over and then expect something different to happen.
So if I'm not making mistakes it's usually because I'm not trying hard enough. But the biggest? Probably taking a long time to learn that if you really want to be understood, then listen.
There was One Particular Pitch (we all have One Particular Pitch) that illustrates this perfectly and I still sometimes wake up sweating at 3.00am dreaming about it. It took place long, long ago in a far off galaxy and you'll recognise the scenario: big client, big budgets and a big but stale brand that at the time was stuck running up a down escalator. At the 11th hour, some brilliant but dangerous thinking from my brilliant but dangerous team was overturned by an over-opinionated chief executive (me) who believed he had an inside track on what the client really needed (and was likely to buy, natch). The result? Some lowest common denominator work and a pitch team performing with all the passion, commitment and intensity of Star Trek aliens. We somehow won the pitch (the work was precisely "on brief") but the account was indigestible and damn near killed us. And anyway that wasn't the point. It was the thousand-yard stares back at the agency that told the real story. I'd lost hearts and minds and it took a long time to put the pieces back together.
JONATHAN DURDEN - President, PHD
This is a tricky question.
I am happily free from regrets about not having achieved something from a selfish, personal-gain point of view.
I have over-stretched myself, given the lazy underachiever that I was as a lad.
I have been a lucky, late bloomer and blessed to have joined with awesome partners and mentors.
I do not torture myself about having stockpiled less of a money mountain than Philip Green.
My regrets mostly concern my role in letting others down, either knowingly or unintentionally, along the way.
For not giving John Harlow more power before he left PHD to found Naked, along with our other geniuses Jon Wilkins and Will Collin. (Thank God we then found Mark Holden and Louise Jones.)
For not giving Tess Alps more capital wealth from PHD, which she so richly deserved, despite her being fundamental to our success. She is a goddess.
For leaning utterly upon the strength of Morag Blazey to do most of the hard things when we most needed them, because I felt pathetically weak or just bottled out.
And recently for not investing enough effort to get to know the new generation of emerging talent at PHD, who are clearly a very exceptional crop indeed.
These are the things that make up my cumulative mistake in not giving enough to the most incredible set of people it has been my privilege to work with along the way.
CHRIS INGRAM - Founder, Ingram
If you're an entrepreneur, you have to accept failure, while never enjoying it. I've lost more than £1million three times on businesses I've invested in or bought - twice through misjudgment and once through fraud.
But the biggest mistake (in fact, series of mistakes) I made was in a dispute with the TV companies in the mid-90s when at CIA. We mismanaged our book, overtraded and tried to slide out of it, as media agencies typically did at that time. Unfortunately, the TV companies had had enough of this and decided to make an example of us. I missed this change of mood completely (preoccupied with international expansion and the City) and it ended up costing us £1.9 million.
Ironically, I'm now asked to talk or write quite regularly about "the importance of failure". The Brits are fascinated by this topic and are amazed that anyone is prepared to talk about their failures, whereas the Americans assume that you must have failed a few times in order to be successful.
SIR MARTIN SORRELL - Chief executive, WPP
My biggest-ever mistake was at a charity cricket match. I was bowling ... and had the England cricketing legend John Edrich plumb lbw. The umpire (the former Archbishop of Canterbury) gave him not out and I didn't call for HawkEye. I've regretted that ever since.
My next biggest mistake was over the Ogilvy acquisition. I over-leveraged by using convertible preference shares, failing to realise that, in a recession, such shares become debt. On the other hand, I comfort myself with the fact that Ogilvy continues to be a stunningly successful company - so I guess, in retrospect, that it was a risk well worth taking.
GREG DELANEY - Chairman, Delaney Lund Knox Warren & Partners
We had just finished a new commercial for a client. We were rather proud of it. The marketing director was also delighted and wanted to share some of the glory with his new and slightly scary chief executive. He therefore requested that we send a video copy to the home of the scary chief the next day (Saturday), so that he could have a preview before it was broadcast the following week. We called the post-production house in Soho and asked them to send a tape to this Very Important Man. Understandably anxious that it should arrive safely, we were relieved to hear that it had been delivered on time and intact. On Saturday morning the chief exec, his wife and his two young children duly assembled in their living room to watch it. The commercial played - 30 seconds of charming and engaging film. Unfortunately, what followed immediately after our efforts was some particularly full-on, hard-core porn. The tape had obviously been used before and for a rather different genre. I never did find out whose late-night viewing habit or little business on the side at the post-production house we had been the innocent victims of. I do know that we lost the business soon after. And we never did get that tape back ...
STEPHEN ALLAN - UK chief executive, Group M
Business is about making decisions, and if you spend your life making decisions, you're going to make some bad ones. I'm not sure if this was actually my biggest mistake, but it was certainly my most spectacular.
When MediaCom was first named Media Agency of the Year by Campaign in 1999, we decided to celebrate with a big party the following March. We hired the Commonwealth Institute and settled on a fairground theme, complete with a helter-skelter, merry-go-round and dodgem cars.
Pursuing this theme, we bought 1,600 coconuts to send out as invitations.We realised that the postage would be expensive and, as media agency professionals always do, we started looking for a better-value solution. In the end, we opted to hire a van and have the company driver hand-deliver all the coconuts to those guests in London and the South-East area.
Cut to the Ark, the landmark Hammersmith office building, a few days later, where I'm waiting to be called in to pitch for the Seagram business. My mobile rings. Our driver has gone through a low bridge and transformed the van into an open-top vehicle. Hundreds of coconuts are rolling down the street. I swear, hang up and do the pitch.
Most of the coconuts are retrieved, we hire another van, and the driver heads out again. Three hours later, another phone call: the driver has tried to park, and knocked over a motorcycle, which has knocked over another motorcycle, which has knocked over another motorcycle, which has - you get the picture. So does the rental company, which refuses to let us have another van.
So, humbled by the failure of my "low-cost" solution, I tell the team to post all the invites.
As well as a big mistake, the Coconut Incident was also an omen. Days later we learned that we had won the pitch. The Seagram business was ours. Shortly after that the company was taken over. The Seagram business wasn't ours. The party was good, though.