This is a binding vote so that when floor prices increase / fluctuate, we do not need to vote on selling a Grail if the price is right. For example, if this vote concludes with 50 ETH as majority, then our multi-sig signers would know to list/sell any Grail who's floor is above 50 ETH without needing to wait the time it takes to vote again. If folks do not want to set a limit then there is the "Do not list" option of course.