It sounds like a dream job, but actually, it's not. You start to tire of a sport you loved, and each morning you wake up with a pile of cash that you want to make a few percent bigger by the end of the day.

You're not adding anything to society, you have no colleagues, there's little to talk about with friends and family, and most people think you're a lazy bum.

Slowly your life becomes consumed - I was doing 16-17 hour days just moving money around and trading - your diet turns to crap and you start to resent what you're doing.

It's at that point you are vulnerable to "breaking the rules" and chasing losses, over-betting or doing other stupid things. Back then I did not have the resources to automate my strategies, so I lost £5k in 2-3 days about 9 months in and thought "time to get a proper job before I do some serious damage", and got back to working for a living.

I have since then automated many of my strategies and it's my favourite hobby, but I am under-capitalised and not interested in using other people's money: it will remain a hobby for some time yet, but I can get 10% RoI a month for some strategies, which definitely beats savings. Just need to wait for the bank to grow, and grow and grow... Maybe one day I will be a "professional gambler" again, but really it's just data science and software engineering for a very strange product.