Because long term tenure doesn't get companies enough of a return. If a company wants me to stay long term, I need regular raises above the rate of inflation, p

Because long term tenure doesn't get companies enough of a return. If a company wants me to stay long term, I need regular raises above the rate of inflation, parental leave, everything you listed. It's so much cheaper to spend the $10k or so it costs to replace me every year or two and not worry about the other things.