I think it's a relative value thing where some video games can be played for dozens of hours. In one of the older Smash Bros games there's a message when you'v

I think it's a relative value thing where some video games can be played for dozens of hours. In one of the older Smash Bros games there's a message when you've played 4995 bouts that let's you know you've paid about 1 penny per round at the original MSRP. There are games I've played for hundreds of hours (not recommended, but if it's engaging enough it can happen). Sonic can probably be played multiple times over if you're going for a high score, but if it isn't engaging enough for you to buy into that the value or cost per hour is pretty low. Some games encourage replayability with multiplayer competitions, some with randomization or procedural generation, some with branching storylines or multiple endings, etc. High scores are a classic way to encourage it, but they work best at a local arcade or when you have friends / family to compete with at home. If it's just you playing through a Sonic game at home it can feel a bit lackluster for many to play it over.