imo Serie A is doing a poor job implementing the var rules (link below). the "clear and obvious" error part gets twisted a lot (depending on if the var acted or not) + the refs lean on var too much, which also isn't allowed.
f.e. yesterdays penalty foul by Morata - the ref initially stopped the play after Dumfries grabbed the ball with his hand and gave an indirect fk to juve, probably already at that point knowing that he wants to watch the footage. was not calling the penalty there a clear and obvious error? I'd say no, it's not the placement of the foul thats up to interpretation (like in Zakarias case, thats easily a clear and obvious error) but the foul itself and it was a softie. imo if he gave a pen right away it'd have been a correct decision (as there was contact), but it wasn't the correct decision to use var for that. half an hour earlier the same "not a clear and obvious error" rule was used for the Lautaros high kick in Locas face, the ref had already given a yellow and VAR (correctly) couldn't intervene. the ref easily could've given a red there and that would've been a correct decision, but since a yellow card wasn't a clear and obvious error the decision stood. however the size of the error for Lautaro's kick and Morata's pen is pretty much the same, I don't see how you can call one an obvious error and the other not an obvious error.
for the record, I'm not a fan of the VAR rules as they are written, IMO the refs need assistance whenever they're fucking up a serious incident in the game and the subjectivity involved in interpreting "clear and obvious error" robs them of that chance in favor of some "keeping the spirit of the game" bullshit. however the double standards with which current rules are applied in Serie A suck.
https://www.theifab.com/laws/latest/video-assistant-referee-var-protocol/#principles