The "Roy Rule" on hiring

Adam Haylock (a customer of my previous employer), gave some similar advice at a company event a few years ago and it stuck with me. So much so that I had a succession plan in place for when I eventually stepped out of my team into a new role. It massively reduce the guilt I might have felt otherwise leaving my team behind and also freed my up to try my hand at something else. While it didn't quite work out for me the way I had wanted, that was my problem and not my team's.

If you can't be replaced, you can't be promoted

I'm pretty sure that's the wording Adam used. Roy Schwartz:

Always go for people who want and can do your job.

Some more advice from the same post:

But here's the secret: The easiest way to get better at something is to surround yourself with people better than you — and learn.

This is where I am now in my career, I'm surrounded by much cleverer and more talented people than I have been around for a while. I feel like I did coast for a few years but once an opportunity presented itself I took it (and did so twice). I've never felt the need to be the cleverest person in the room, but clearly know what my strengths are and I'm always open to conversations and when appropriate, taking the time to learn new things.