A while back, maybe 15 years or so, I was on the brink of leaving my job at Waterstone's Online when my boss called me into his office. I'd accepted an amazing (and it turns out life-changing) new role at The Science Museum. At the time I was excited about the new job but also quite sad at leaving my old one. It'd been my first grown-up role: in London, in an office, working with managers and reports and all that stuff for the first time. But also it'd been an astonishing time - when I started it was pre-Amazon, pre-boom - the web team was me and one other. When I left it was 80 or so. This was big and exciting - and I loved it.

I expressed this to my boss, and he said something that I still remember.

He told me that leaving a job was a necessary thing to do every so often, however much you love it. He talked about the build-up of stuff, the endless entropy that comes with work - how those projects you never quite completed, the emails you never sent, the ideas that never came to fruition - gather around you like dust: a continuous aggregation of matter - physical, mental, imagined, actual.

Leaving a job, he said, lets you literally and metaphorically clear your desk, an absolutely vital part of moving through your working life.

This has remained with me to this day - and not just when moving jobs. When I get bogged down I find it helps to think about where stuff has built up - not just the inbox but also all those places we put stuff to read later: Evernote, Trello, text files, Dropbox, Kindle, folders on your Mac desktop, piles of books around the house, articles pinned to walls, newspaper clippings. When you've found them, clean them, as if you're leaving that job forever. Empty your physical and mental drawers - put a line under it all, and move on.

Just removing stuff, ruthlessly, with no remorse, no looking back, no what-if's can sometimes be the best way to clear one's life and mind.