Most backup software allow you to configure backup retention. I think I went with some pretty standard once per day for a week. After that they get deleted, and it keeps just one per week of the older ones, for one or two months. And after that it's down to monthly snapshots. I think that aligns well with what I need. Sometimes I find out something broke the day before yesterday. But I don't think I ever needed a backup from exactly the 12th of December or something like that. So I'm fine if they get more sparse after some time. And I don't need full backups more than necessary. An incremental backup will do unless there's some technical reason to do full ones.
But it entirely depends on the use-case. Maybe for a server or stuff you work on, you don't want to lose more than a day. While it can be perfectly alright to back up a laptop once a week. Especially if you save your documents in the cloud anyway. Or you're busy during the week and just mess with your server configuration on weekends. In that case you might be alright with taking a snapshot on fridays. Idk.
(And there are incremental backups, full backups, filesystem snapshots. On a desktop you could just use something like time machine... You can do different filesystems at different intervals...)
