the mechanic that you always try to improve your best score is good at start but only if your first 5 or 6 games is not that great. because that you dont have many fans and the sells are low even if you get 9.75 you will get max 300k, then without any research you will need to create a BETTER game. thats impossible with the tech you got. I dont even get into the topic of longevity of the playthrough. Even if its not a game patch there should be a mod about this. I want to e able to get 10/10 when i create a great game even if i got it just before that. Even if the games are diffrent in every way there is no chance that you will get it.
10/10 games are very difficult to obtain, even if you micro-manage. Get 9.75 for many games in a row is quite easy, but that getting that perfect 10 or even a 10.25 is I think dependent whether All Games is being nice.
This happens in real life as well. Most reviewers are very positive and a few stand out nitpicking on the little things and thus giving a lower score.
Basically getting a 9.75 or even 9.5/9.25 means you got a Top Hit review. those perfect 10’s should be rare.