Dr Chris Evans - My Biggest Mistake: Danger of delegating

Dr Chris Evans has created 16 science-based companies with a total annual turnover of pounds 200m. He employs 1,700 people, and presides over more than 100 scientific publications and patents. His latest company, Merlin Ventures, is headed by Jeremy Curnock-Cook and a team from Rothschilds.

My biggest mistake was to believe I could hand over leadership of some of my new start-up companies to plausible chief executives, who would then continue my entrepreneurial themes and grow them in line with my original vision and ambitions. I was wrong. It wasn't obvious: you don't employ someone who's such a buffoon that you know within a month. But in time you find people building up an illusion - I tend to deal in reality.

What I hadn't budgeted for was the simple inability of many so-called high-flying CEOs to knuckle down and do the job properly. One of the first things you notice is that you're not selling enough of the product or services. There are some great excuses for why that's not being achieved. And you notice they feel comfortable building more and more structures - distribution structures and technical structures and international structures - and you realise, "This guy is not a doer; he isn't going to get into the customer's face and convince him to buy the product".

I have learnt a lot from this and have had to dig deep, literally roll my sleeves up as an entrepreneur and get back in there to help make a success of what I started and others had messed up. I was disappointed with the waste of my time and effort and investors' money in turning these businesses around, but at least that is now being achieved. Now, when it comes to the recruitment and interview process, I will grill them on various aspects; I will bring things right up front and make it very unappetising. If somebody says, "I don't like the sound of that" it's a good time to say goodbye.

It does mean that I set up far fewer companies: my rate of creation will be dictated by the availability of high-quality people. My aim is to ensure that fundamentally good companies created by myself and Merlin will never again be left alone without some positive supervision and motivation from myself and my team.