I love my camera. I love it even though I took terrible pictures with it for a month. I love it even though I have to adjust the aperture, worry about depth of field and annoy my family while I twiddle with its metal knobs. I love it because it makes me think: about light, colour, composition. I take fewer pictures with it than I take with my phone, but much better ones. And I’m not alone in my love for my camera. While sales of point and shoot technology continue to decline, the market for fiddly manual cameras is growing nicely.

We live in a world where almost everything is designed to be simple. When I work with designers, I often come across a kind of religious belief summed up in the mantra: don’t make me think. Slick web design keeps us in a kind of unthinking trance, where we buy things on Amazon or post photos on Facebook without ever having to stop and consider what we’re doing. While this is great for retailers, it’s also good for fraudsters. Phishing scams rely on our trance-like state: please reset your password. Follow this link. Enter your password. Thank you. Click, click, click, oops.

Something similar has happened to driving. It’s possible to hurtle down a road at 50 miles an hour without thinking at all – until it’s too late. One of the most successful safety design campaigns of recent years aimed to tackle this. The shared space movement puts ambiguity back into road use, for pedestrians and drivers alike. In South Kensington, all street furniture and crossings have been removed and replaced with ambiguous regions where it isn’t clear who has right of way. Drivers and pedestrians snap out of their trances, cars slow down and the accident rate has fallen by 43%.

Difficulty isn’t just about safety. It can make our lives and jobs more meaningful. In Dan Pink’s influential book Drive, the author argues that humans are motivated by autonomy, mastery and purpose. When we design things to be simple, we take away the fulfilment and satisfaction that come from mastery.

I once worked with a company whose software told banks how risky their global investments were. At the time, the bosses at these places were estimating risk by stitching together spreadsheets in haphazard ways. Their view of the world was partial, flawed and out of date. We made it instant, simple and beautiful. Why was it rejected? Because it stripped away all the difficulty. With our software, an idiot could be head of risk at a global investment bank. Nobody bought it, banks continued to measure risks the hard way and the world economy collapsed. Sometimes I think if we’d found a way to make it harder to use, our software might have saved us all from a decade of poverty.

Sometimes, harder is worth it. If you watch a currency trader or film editor work, you’ll notice they tend to use shortcuts to perform tasks: single key presses or “chords’ such as shift-alt-command-V. Designers sometimes speak in hushed tones of “the mother of all demos” when Doug Engelbart unveiled the computer mouse. But the mouse was only one of the technologies he showcased that day in 1968. Engelbart felt it was a waste of time for a user to move their hand from keyboard to mouse and back again. So his team devised a five-button keyboard where you pressed chords simultaneously to write words, delete, copy and paste. In the end, the mouse triumphed, as computer manufacturers believed that only hardcore programmers had the patience to learn the key combinations. If only they’d had a little more faith in our desire to master things, maybe they’d have saved writers and programmers a lot of time and tendon twinges.

I’m not suggesting that everything should be designed to be more difficult to use. Toilets have a perfectly good user interface, except in Japan (why do Japanese toilets have a remote control? Where else are you going to be when you flush them?). It’s one of the miracles of the modern age that we are able to wield extraordinarily powerful tools without having even to read manuals. However, sometimes designers have a duty to make us think about that power. When we do, we’ll use things better and enjoy them more.