It stops fatties creating accounts just to downvoat everything at once. You need to start joining in more. The more you comment (well, the more people upvoat your comments) the more contribution points you'll earn.  Once you reach 100 points the voting limit is removed. It encourages participation instead of just lurking silently. I just upvoated you so you've got at least 1 contribution point now! Just keep commenting and as long as they're good comments that contribute to the discussion, people will upvoat you. Then, before you know it, your limit will disappear!