For crashes, perhaps. Sometimes a glitch or a bug can get baked into a save game, though, and the only way to get rid of it is to go back to a save before you got it. If the glitch or bug was one that takes you a while to notice, you may not have a history of saves to go back to the most recent bug free save if you rely on quick or auto saves. Making a hard save at least once per game day insures that you can go back to pretty much any time in your characters story.

In fact, I had one such bug with Piper in my first play through. I noticed that she had lost her sandbox routines. She was just following close like the vanilla followers from previous games (Fallout 3, Skyrim) and always standing about six feet away staring at my character. She was otherwise functional ... drew her weapon when I did, went into sneak mode when I did ... just didn't do the sandbox thing like she should. I tried everything to fix her, but couldn't find a solution aside from going back to a point before she developed the bug.

Fortunately, I had a history of saves and didn't have to go back too far, but I did have to go back about four hours of play-time. Had I been relying on auto and quick saves, I would have been stuck with the issue.

I have my Acronis True Image set up to save my entire hard drive every night.

You could also set your backup program to save only your Fallout 4 directories if you so chose.

Might be a good idea if you play to say 4 PM every afternoon to have it back up your entire directory at 4:30.

That way if you forget to do a hard save, or if something else happens, you have a fair chance at having a recent backup of EVERYTHING.

It seems so many people only fire up their backup program once in awhile instead of using them daily.

I don't understand why ... it is easy to set them to backup automatically every day.

Same, I can't recall ever suffering a corrupt save game in any game using any of Bethesda's game engines. I mean there is the Outcast BoS virtual Reality DLC in FO3 where loading the final auto-save made during the virtual reality session bugs out a script making the DLC incompletable (Script involving important NPC never triggers when loading the save), but that's not a corrupt save game, that's just bethesda being their traditional shoddy selves when it comes to writing code.