Comment by rich_sasha

"Loyalty" is also worth something to self - to the loyal employee. It is a signal on CV that given the right environment, you commit to projects and people value your input. That's not to say, stay at all cost, but that when you leave, you pay a price too, and sometimes it's not worth it.

In my line of work, it can easily take 6-12 months until people are really productive, I'm reluctant to hire someone who will be a time sink for all this time then leave 3 months later.