Well, if I am one of the watchers that's easy. It just means that
I absolutely want to bid on that, or
I absolutely wanted to bid on that but forgot, or
I am waiting for you to relist it at a lower price, or
I wanted to see if it would sell/at what price it would sell, or
I thought it looked interesting but I need to do more research, or
I thought it looked interesting but decided against buying it (and haven't cleared the watch list in a while), or
I thought I might buy something like it but not this particular one or not right now, or
I clicked on it by accident.
Also it's not always clear what a "reasonable" price is. Products that are sold frequently usually have a more or less well-defined market price. But for more niche stuff, it might sell for crazy money one week if there happen to be several people who really need/want it NOW. And the next week it won't sell at all because the only potential buyer around thinks it's at most nice to have and would only seriously consider it at a bargain price.