How does SDS determine which pitches a pitcher has in his repitoire?

[x814xMafia_PSN]

Take LS Rich Hill for example.

Beginning of last year he had three pitches. I think the were a fastball a 2 seam fastball and a curve.

Then towards the end of the year they added a 12-6 curve, I think, that gave him three pitches.

Now for 21 he has 5 pitches. A 4 seam fastball, a sweeping curve, a slider, a cutter, and a 2 seam fastball.

Do they just throw darts at a borax of pitches and whatever sticks they assign?

Seriously though, how do they determine what pitches a pitcher has in his repitoire?

[Red_Ted_is_back_PSN]

Based on which pitches they threw last year, I think.

[Nanthrax_1_PSN]

Pretty sure they use baseball savant... Which shows pitch arsenal and usage

[Red_Ted_is_back_PSN]

@nanthrax_1_psn said in How does SDS determine which pitches a pitcher has in his repitoire?:

Pretty sure they use baseball savant... Which shows pitch arsenal and usage

I think Ramone may have even said just that in the last stream.

[GCRBI5_PSN]

Baseballsavant lists Rich Hill's 2020 repertoire in order of frequency as fastball, curveball, cutter, slider, and sinker. In 2019 Hill threw a fastball, curveball and slider above a 2% rate.