This is an issue that has been addressed many times before:

-ve XP, node reputation, voting and learning
Why is my reputation falling?
Reasons for downvoting

Everyone has their own individual and sometimes fickle reasons for downvoting, from personal downvoting or disagreeing with something a person has said to plain XP Whoring; people wasting their votes in order to gain just that bit more XP. If the downvotes are in the minority, I wouldn't give much thought to it; just remember that the XP system is essentially flawed in various ways, and after you reach Level 6 (Friar) most people begin not to pay much attention to XP anyway.

However, if you really cannot see the reason why your post is being downvoted en masse and you are concerned, you can always ask the opinion of the CB; some people may give you advice on why it is being downvoted, but I think it should be the perogative of the voter to decide whether they should tell the person who is being downvoted why. A lot of people don't have that much time to spend on the site, and a lot of downvoted nodes (or the ones I downvote, at least) such as flames, personal attacks on people, completely irrelevenant replies etc. don't even warrant a /msg.

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rozallin j. thompson
The Webmistress who doesn't hesitate to use strict;