The "as time goes by" portion of your argument is null and void, though. The trade values site certainly didn't foresee Grisham's and Davies' strong 2020 seasons judging by their valuations of both players, especially before the trade. Even if the site's justification in changing the values was to essentially "right a wrong", the optics of the timing were simply terrible. Since then, in essence, the "wrong" has been "righted" with the justified change in those players values after their 2020 performance. If you go in and do a "trade back", Davies/Grisham are now nearly double the surplus value of Urias/Lauer. I think the crux of the issue is that the trade value site seems slow to update values on minor league players who "break out" in a quick fashion, such as what Grisham did, while they are also slow to lower the values on highly thought-of Top 100 guys like Urias when they don't live up to that advanced billing early on. They certainly didn't need to go in to their system the day of the trade and raise the value of the guys the Brewers traded off, though, while lowering the value of the guys the Brewers got back. At that time, those players did nothing to justify the value adjustments. Player performance is only one aspect of valuation. How these players are perceived by MLB GMs in a real life trade scenario is absolutely another. To further address that and Peavy's question above about why people feel the need to defend the site and their explanation, my answer would be this: what they are doing is really tough; actually, impossible, and certainly arbitrary. There will be times when valuations seem dead nuts, other times they will seem out of whack. You have hundreds if not thousands of assets whose values are constantly evolving, and you can't possibly keep them up to date daily. Think of how much the value of Devin Williams and Corbin Burnes changed just month to month this year. Obviously, it's easier to stay on top of it in the offseason but you still have other factors influencing valuation change other than just raw player performance. Yes, it's not perfect. Yes, it's arbitrary. It can't be perfect. Value of a certain player varies just from one TEAM to another based on the team needs and how well that player fits with that team. There are too many intangibles to even assign a definite grade to a player based on his fit for one team, let alone a general grade that fits for all 30. It's not just that way for the site. It's that way for every valuation system. That's why we have dozens of different ranking sites none of which say exactly the same thing. There's subjectivity at play anytime you're dealing with any system of player evaluation. The same goes for Pro Football Focus. So when I see a website that does valuation better, sure, I'll come out and say, "the grades on baseballtradevalues.com are junk." Until then, I respect the difficulty of what they are trying to do and think it's just another valuable tool for fans rather than looking at it as the end all be all and garbage if it doesn't say exactly what I think it should.