What determines the type of card....

Often times I see on here people predicting whether a player will get a signature series, prime, award or milestone card and I'm wondering if there are any tell tale signs for which series a player will get.

Milestone is fairly obvious. Max Scherzer and Miggys cards were no Brainers. Awards can be issued to pretty much anyone with some type of hardware which covers most good players when including gold glove, silver slugger etc.

So what are the indicators that determine prime or sig series? Or are people just really good at guessing? I ask because I truly don't know and am curious.

Newbie blues.

Guesses usually are from what we have seen in previous years. Milestones are new this year, but there are only milestones that we have seen and those milestones are only achieved by a handful of players which narrows down who would get a milestone card. If a player had one or two great years, but have won a CY, MVP, or GG they could get an awards series card. If they had three or four years of outstanding seasons in the middle of their career, they could get a prime series card. If they had a long distinguished career, they would most likely get a signature series card. Awards series cards are based off a single year while prime is based off three years and signature series cards are based off a career.