Designers can be difficult to live with. We notice the confusing sign, the awkward sentence, the extra step in a process. We point out what isn’t working, sometimes when nobody asked. I can see how that gets tiring. Sometimes you just want to order lunch without someone critiquing the menu. But spotting a problem is often the first useful thing a designer does.

There’s a story about Michelangelo being asked how he carved David. His reply, in the often-repeated telling:

“All I did was chip away everything that didn’t look like David.”

Whether he said it or not, the idea gets at something true about creative work. Making something good involves deciding what to leave out.

Every project starts with possibilities. Different messages, layouts, journeys and ways to solve the problem. As designers, we explore those possibilities, test them and discard most of them. Even the ones we like. Sometimes especially those, because it’s easy to become attached to an idea before establishing whether it works.

So we ask awkward questions:

• What are we assuming?

• Where might someone get stuck?

• What could they misunderstand?

• What would improve if we took something away?

Gradually, the answer becomes clearer.

Designers aren’t unusual in working this way. Engineers look for points of failure. Scientists test whether an explanation holds up. Pilots rehearse what to do when things go wrong. Paying attention to flaws helps people make better decisions.

Astronauts take this thinking further. We tend to celebrate their bravery, but they spend much of their preparation asking what could go wrong. They rehearse failures, question assumptions and work to reduce every risk they can. They prepare for the risks they cannot remove.

Being careful gives them the confidence to do something extraordinary.

There’s a useful lesson there for creative work. You can believe in an idea and still look hard for its weaknesses. Finding a problem early gives you a chance to fix it before it becomes someone else’s frustrating experience.

There is a limit, though. Anyone can point at something and say it doesn’t work. Constant fault-finding can wear people down and kill an idea before it has had a chance to develop.

Useful critique has to go further. It should explain the problem, show why it matters and help find a better way. It also needs judgement about when to challenge something and when to give it room.

That’s the kind of negative thinking I value. It gives us a way to question an idea without giving up on it. To remove what’s confusing, unnecessary or weak until the thing we’re trying to make comes into focus.