Based on the "no interest for X months" credit model by the sound of it. If that loan isn't paid off before a certain date, they get you on some stupid high interest rate for the entire amount & duration.

They're 100% betting users will over run because that's what they do.

I don't use iDrive. Does the service/application inform the user that they're over quota, or close to it- or does it quietly over run?

Yes. And I've had various drives die without warning, including SSDs, flash media, spinning rust. You never know when a power spike (or corruption, or bad luck, or a spilled drink or...) is going to come along and smoke your storage.

I dropped my hard drive out the car window now its making a weird noise please help its going click click listen to my video is this normal!!!

Folks speak highly of Veeam backup software. I've not used it but there have been quite a few endorsements for it on this sub.