So I'm wondering what prevents people from scaling like crazy besides the obvious monetary reasons. I've just started and after a few months I'm debating to start putting in a lot of money into mining. I think mining is a dangerous business because the more money you put in the more you make.
The time and effort required both in initial setup and maintenance would be the biggest factor. Also the fact that it takes some time to earn back your initial investment and most people after that would like to earn some profit. Space would be another major factor. The heat output. The fact some places people will be limited on electricity output.