Votes are influenced by a number of factors. A common scenario: a question of poor quality suffers initial downvotes, then is brought into shape, but some of the downvotes remain, canceling with subsequent upvotes. Somewhat less common: a question is essentially a lazy, vague remark which somehow gets an attractive answer (not necessarily a great answer, but something that many people find amusing enough to upvote). And sometimes the asker's attitude gets in the way of appreciating their question. Etc.
As T.Bongers said in a comment, the question to which you refer has $+5-5$ votes. When you reach 1000 reputation, you will be able to see the vote breakdown on each post. Meanwhile, you can see the chain of events, including voting, on the timeline of the question. There is no visible link to the timeline, so you'd have to either manifacture the URL, install a userscript, or (perhaps the easiest) use this bookmarklet.