Couple of thoughts.
I think people understood that Teo had 4 WAR upside. He always had big time tools, it was just a matter of whether he could unlock them at the ML level. I think Derek Fisher had the same type of upside. He had great exit velo, sprint speed, etc. He had all the tools, but was never able to unlock and utilize them with any success in the majors. Randel Grichuk was similar, albeit his tools weren't quite as loud.
Players with this profile obviously are risk/reward types. There's typically a lot of doubt whether they'll reach their potential - otherwise, the cost/value to acquire them would be sky high. At first glance, it looks like we got a few toolsy players in these recent trades. There's probably a high probability they fail, but they have some upside and as you say, you only need 1 of those lottery tickets to "hit" really.