Not a rule exactly but I like to have a risk bucket. Shares that will probably tank, but are interesting for various reasons. Like Wellington based, or at least NZ. Innovative. #8 wire. That sort of thing. Including the odd crowdfunding one. I am usually an early adopter. In truth they are mostly dogs or fall over completely, but they are fun.

If 1 out of 10 is a star, fantastic. If not, still fun.

Some of my risky ones on the NZX - BLT, CRP, AOR, PIL. And XRO now on the ASX, not so risky now.