An objective is what you are trying to achieve, stated qualitatively. Key results are the measurable outcomes that would demonstrate it.
The discipline is in the key results: they must be outcomes rather than activities. "Ship the integration" is a task; "reduce time to first value below a week" is a key result.
Tying them to compensation. The moment an OKR determines pay, people set achievable ones, and the mechanism that was supposed to encourage ambition produces the opposite with complete reliability.
This is the single most common way OKR adoptions fail, and it is usually introduced with good intentions in the second year.
No. It is the reliable way to make people set unambitious ones.
Three objectives with about three key results each is already a lot.
They were probably too easy. Consistent full scores mean the exercise is not measuring anything.
Half an hour with your own data usually saves reading three of these. The guides will still be here afterwards.