It's not faith in any sense of the word. He projects for 2 wins and was a 3 win player as recently as 2017, and his skills have not changed since then.
We have projections for every player and, centered around those projections, we can reason our way to upper and lower tier outcomes. Puig is expected to be worth about 2 WAR. It would not be that weird to see 3 WAR because he did it recently while exhibiting the same tools. If you get super optimistic and say, presume he has a good defensive year and figures something tiny out on offense, 4 WAR seems super optimistic but still possible... maybe you give it a 5-10% chance of happening.
Alford projects to be BELOW replacement level. Do you know how bad you have to be to get a negative projection? Here are some other players with ZiPS projections around -0.3 WAR:
THE Ryan Goins
Richie Martin, coming off a -1.0 WAR year
old friend Mitch Nay
Sicnarf Loopstok (yes this is a real name)
old friend Kendrys Morales
old friend Dioner Navarro, who hasn't played since his -1.8 WAR 2016 but did play in AAA last year and had a nice 69 wRC+
old friend Travis Snider, out of the league since 2015
Danial Palka, who had a 2 wRC+ last year. That's not a typo.
old friend Ezequiel Carrera
In order to envision a scenario where he is worth 2 WAR, you basically have to imagine that he has some sort of Freaky Friday thing happen with Byron Buxton. It would be borderline shocking to see Alford get to 1 WAR, but I guess that might be possible if he is used mostly as a defensive replacement and pinch runner? I dunno. The guy can't hit at all. Like, he swings through every type of pitch, even hanging sliders and fastballs.