Thanks for all the responses. It is what makes this board so helpful. So, please do not be offended by the following comment:
There are times (almost always with this subject matter) that a question will be something like (analogy), "We have days where there is a large predicted snow storm the following day. Do we give the day off with pay or not?"
Inevitably, some will give what they do, i.e. we do not pay for acts of nature or we pay them as it was not their fault they couldn't work, but some will say, that happened to us and we moved to south Florida. While that will work, it was not the original question.
The original question here was, "Does anyone think that incentivizing their receptionist by a percentage of all back balances collected, is helpful."
The methods given by very nice users doesn't answer the question it alleviates the need for the question. I realize they overlap somewhat, and I still learn from the answers, but so far, tcosta is the only one to comment on it.

Again, thanks to all.