Give up what makes you unique and you’ll end up no different to any other pizza-d out pitchbook pony, says David Charters.

When I first started work at what was then called S G Warburg, one of the senior directors took me aside and offered some words of wisdom. He told me that there are three things that matter in life, and the key is to get the balance right between them.

The first was work. Having chosen a City career, rather than something else that was less demanding – and potentially less remunerative – I had to accept that my job would take up the vast majority of my waking hours, consume energy and enthusiasm, and in the early years in particular the rewards would not be vast.

Was I prepared for the trade-off involved in sacrificing those critical early years in my one unrepeatable life?

The second was family. He had seen countless marriages and families sacrificed on the altar of the all-consuming firm. When deals are under way, investment banking is by its nature utterly uncompromising: the stakes are simply too vast for it to be otherwise.

If I was to get the balance right, I had to draw some lines beyond which I would not go, or I would risk what in theory should be most precious in life, my family, for the sake of another Lucite tombstone or place in the league tables.

Finally, there were those things that made me unique as an individual – my interests, hobbies, friendships, causes I supported, ways in which I chose to spend my free time. He believed this was the easiest area to get wrong.

He’d seen too many bright, multi-faceted new graduates join the firm with impressive backgrounds as student journalists, politicians, athletes and musicians, only to become one-dimensional cannon fodder for the deal machine.

A year into their time at the firm, too many had put on weight and looked unhealthy after countless all-nighters in the office, too much delivery pizza at midnight while working on a pitch-book, and not enough time off to relax, unwind and get a life.

These days, it’s considered appropriate for major firms to release people for volunteering, or serving as charity trustees or pro bono advisers, as part of the firm’s corporate social responsibility programme.

The difference between theory and practice doesn’t make it onto the corporate website: “Sure, you can have one day a month to help the hospice. Just don’t expect anyone to cover for you, and you’d better not let me down if I need a presentation the next day.”

It comes down to drawing lines, and in particular identifying those times when it is right to take a stand, and those times when it is right to bend over because a live deal is happening and it is all hands to the pumps.

In the early years of an investment banking career, the temptation is always to say yes, even for the most trivial, unnecessary, make-work nonsense, because everyone wants brownie points and no-one wants to risk a black mark from someone senior.

Perversely, getting a reputation for intelligent, considered questioning, sanity-testing ways of doing things, and very occasionally, for non-revenue generating tasks, saying no, or at least not until tomorrow, may be no bad thing. At the end of the day we are all our own masters. It’s just that many of us act as if we don’t know it.

David Charters’ latest book, The Ego Has Landed, is published by Elliott and Thompson, price 9.99.