Why there is a change in reputation both positive or negative when an answer is deleted ? If someone posts an arguably incorrect answer and people down vote that answer then that down vote should be retained . It has become so easy that someone posts an answer which reduces his/her reputation but one can negate that reduction by deleting the answer , otherwise if it is retained one will be more cautious and logical while posting an answer . Just my thought , it would be wonderful if we can implement this feature .
The whole point of the voting system is to give notoriety or to disprove an answer/question.
Bad answer should definitively be deleted and I think taking back the penality is a good way of encouraging the act of removing the answer.
An incorrect answer that received down-votes or negative comments can be edited and then reviewed by users and have the chance to get up-voted after. I think the voting/penality system works just fine this way.