At this point most of Russian occupation forces are volunteers who signed up to get enormous sign-in bonus and huge salary. Huge for Russian rural areas.
They promise up to 4 million rubles sign-in and 220000+ monthly.
They are eager to go killing neighbors for $2500 monthly salary.
It is not so easy. There are involuntarily drafted people, there are convicts who joined in exchange for a pardon and there are volunteers attracted by huge bonus and salary.