You don't have to, but IRS treats you as having taken anyway

Your base won't be higher (when you sell it) if you don't take it.

Yes, IRS considers as if you take it no matter you take it or not.

If you put into rental late the year, for that year, the depreciation amount is prorated and is going to be small.

You have to take consistently: you can not skip a year, then double take for next year.

If you don't take it, you simply lose it.

Depreciation is so common, IRS has already plugged these obvious loopholes. Don't think we can outsmart IRS.