Hmmmmm... good question... But I know how cheap Walmart products are, and every single can of Krylon I bought from them was just total garbage.. I don't know why... Possibility could be shelf life. But I have bought some cans from a Hobby Store, which seemed to be of a higher quality to me.. Which is also the reason why I stated "In my experience", and means that one does not have to take my word for it.
Personally though I have not had a very good experience with Krylon paints, I just don't use them anymore, Seems like too much of a hassle, if and when I can I will ether use Tamiya paints, or if the budget is alittle low, Testers Lacquer Sprays. But this is only my opinion based on my experience anyway, and you don't have to take my word for it.