> My experience in Europe has been with Chip and PIN, I wonder why we're gravitating toward Chip and Signature.
Americans love credit cards and those who use them tend to have a lot of them. I personally have six credit cards and three debit cards (and, yes, I have a reason for having each card). My father has a wallet more than 1 in (2.5 cm) thick from all the cards he carries. According to the Boston Fed the average cardholding consumer had 4.0 credit cards and 1.6 debit cards in 2012[1]. Forcing people to memorize a PIN for each card they have would discourage people from signing up for more than one or two cards which would be a nightmare scenario for the credit card industry.
[1] http://www.bostonfed.org/economic/rdr/2014/rdr1401.pdf (page 92, table 11)