This is a common occurrence for me since I don’t have much time to play. I often get about halfway through and then stop playing for months. When I come back to it I always want to start from the beginning and then the cycle happens again.
One example for me is Fallout 4
I can’t finish a proper Yakuza because I just get so bored with the walking around the same exact neighborhood maps of Osaka and Tokyo. Each yakuza is a little different than the last, they upgrade what you can and can’t do, I want to play them, but they get a little too weird or repetitive so I was out after 10 hours or so, and they’re the first to go when I need space for something else.