The following illustrates the dramatic impact of a situation described earlier in
Chemistry.SE is a vivid beta site with ~ 2700 questions. The reputation of the Top 5 users lies between ~ 9500 and (curently) 4500. I'm the happy guy on rank 5, having given > 200 answers.
The community is quite active and the regulars do their best to prevent the site from degrading into some shabby do-my-homework forum.
When a prolific user (fellow scientist from another continent) decided to leave for personal reasons all his votes were wiped.
I can definitely confirm that he was neither kicked or forced to close his account. The answers and comments that he gave before show that he was a well-mannered person with both a passion for chemistry and Chemistry.SE, voting a lot to improve the site.
Fortunately, his answers and comments are still there - for good reason. Unfortunately, his votes were not measured according to the same standards and got wiped.
When he left, I personally lost 440 (9% of my total) reputation from upvotes on my answers on a single day (2014-03-21)!
Admittedly, this annoys me a lot! Others have lost accordingly.
As outlined above, Chemistry.SE is (still) small and the rules for keeping votes of leaving users with a reputation >> 10k simply can't be applied for our turf.
So: Can we please get the up- and downvotes by our former colleague and fellow scientist back?