Fundamentally, most KPIs don't measure/reward the activities that lead to the desired outcomes, they tend to measure symptoms rather than causes. It's like when the education system discovered that the most literate kids had lots of books in their houses, they started handing out free books... when obviously people who are highly literate will own more books. The books don't *cause* the literacy, literacy causes the books.
When I've made KPIs, I always tied them to things that would increase the bottom line for the company. "We tell our clients you will be doing X, that is in the contract that you do X, so if you do X, I will pay you for it". I shouldn't have to bribe people to do the job I am already paying them to do, but it's amazing how calling it a KPI and attaching their bonus to it, and then mentally treating their bonus as part of their salary in the first place, really works wonders.
J.Ja