Seller suddenly raises the BIN - is this common?

I was just wondering if this kind of action is usual - what do you think? I´ve been watching a jacket which is on 30 day auction with BIN / best offer. I´ve been asking the seller clarifying questions about the item and showed my interest. The communication isn´t too smooth - it takes days for the seller to reply. Now she/he has suddenly raised the BIN and announced me she wouldn´t accept an offer any less than a former BIN was... For me this is a bit confusing - tell me your experiences, does this happen often or should I forget the jacket cos of this?|||The seller knows you are very interested and this would be an International sale, so they raised the price. It happens. It is up to you, to decide what the jacket is worth to you.|||You may not be the only one asking questions and watching this item. Some sellers see lots of interest and no sales on an item and raise the price. It brings on that "I'd better buy it before the seller raises the price again" mentality in some people.|||It could be a lot of reasons. It could be what triyarn mentioned; it could be that they've been watching similar items and the similar items have sold for more than their item; it could be that they were getting a lot of offers that they felt were too low, and thought a higher price would bring the offers up.