1 - Buy stuff because others really like said stuff. Whatever that stuff is.
2 - Figure out what works well for someone else doesn't work well for me.
3 - Goto line one.
It's a tale as old as time and I still do it.
In the past I have shot myself in the foot by being budget conscious and exercising my ADs by buying cheaper options. I am finally learning not to do this.
If you buy an expensive razor and don't like it, chances are you can sell it for a decent used price. If you buy budget stuff, you save on the initial purchase, but there is no resale market so you eventually end up with a box of cheap shave gear that is perfectly usable but which you can't sell even if you don't really want it anymore.
Engage whining Brit mode: It's particularly difficult in the UK and that's one reason why I consider purchases really carefully at the moment. Whatever I buy I am probably stuck with it. The domestic demand for used wet shaving stuff has definitely taken a hit the past 18 months. I have listed pristine, barely used £110 razors on eBay and struggled to make £50 on them, but what with shipping and tax everything is so expensive that it's equally difficult to offer a competitive used price to international buyers without sucking up nearly at least a 60% loss on a razor you may only have used a couple of times. When I see the US members able to list things on the BST for >80% of the purchase price and make the sale, I envy you, and of course it's easier to justify an expensive acquisition if you know the resale market is there.