When you are reviewing posts, you are faced with three options: Skip, I'm done (after some change), Nothing to review.
Ideally, when you make a change like edit, flag, comment, or vote, the "I'm done" option becomes available, and you press it, eliminating the question from the review list. However, this system can be mis-used.
Basically, you can use the review mode as a window to all new questions and answers that might require edit. As such, it is a lucrative and efficient method to find and make unlimited edits, without need to actually mark the question as reviewed, and just select "Skip".
Yes, you are not able to review anymore after you have reached your daily limit of votes, but there is no need to vote at all.
Why do I think this is a misuse? In principle, you might think, well a lot of edits, that is good! But this comes at the cost of doubling the amount of review needed, as other users will inevitable go through it again.
My proposed solution is to make the skip option to really mean a skip (i.e. I will not intervene in the post). Alternatively, whenever you make a comment, flag it, edit it, or vote, eliminate the skip option.
TL;DR
Using the review mode you can edit unlimited questions, without need to select the "I'm done" option, but just select "Skip". This can be misused to go for reputation in an efficient and fast manner. "Skip" should be more rigorous.