I own(ed) my own business. It gets asked about at every job interview. The simple answer: I prefer a regular paycheck.

I first started introducing Linux (as file/print servers) back in the mid-90's. The rate of support calls would drop from weekly to quarterly. A few of my clients I actually had to introduce a retainer. I was making "most of my money" on 'new hardware' upgrades. I was smart enough to stagger roll-outs so I would have somewhat consistent work at Q1 every year. But not enough to reliably pay the bills. The Microsoft Support racket was too lucrative, and would have forced me to be dishonest. I can't live like that.

I gave the clients a choice: I run linux at home, and this is what I suggest for your servers. The level of honesty won me respect but not a paycheck.