I'm not talking about the hardware people. There are different levels of IT people. The money is in data analysis and software engineering. You're right that it's rare to make the transition. I would think the majority of IT folks are conservative by nature. Deciding to move to trading is pretty risky especially when you get a nice income and in most cases, the work isn't that strenuous. Even when I worked at Goldman, I never had to work more than a 10 hour day but I did have to sometimes come in on a weekend. When I think of back office, I usually envision the OPS people. They also have IT guys supporting them. But those OPS guys are treated pretty badly. Low pay and the chance of moving up are pretty slim. Back office IT guys make decent money. Depends on what they are doing. Database admins make good money.
Sorry I didn't mean hardware people either - they were software systems. Front Office = Lots of Upside/Downside, good carry IT = No Upside/Little Downside, great carry Ops = Tiny Upside/No Downside, terrible carry Take your pick