HDD gets fragments too quickly after defragmentation

I defragmented all my drives yesterday before going to sleep and it said 0% fragments on all, I looked it up today and there is 3% on C: and 4% on D:. This started happening a lot recently, I defragment the drives and even after a few hours, with almost no use at all, they get some fragments. I know these small amounts won't really affect the performance but I want my PC to run as fast as possible. The drive is an old Hitachi HDP725050GLA360 from around 2009, but for now it works pretty good (C: r/w speeds are 90/90 and D: - 70/70). By the way, I want to mention that there is a System reserved space and for some reason it always says 9% fragments and defragmentation doesn't help. Could it be a software issue? According to CristalDiskInfo it's health is good with over 19500 power on hours. Here's a screenshot:



Is that something I should be worried about? Should I start saving up money for a new one? I know you would say I should buy a newer and better PC but I'm kind of stuck with this one for now.

Defragmentation statistics are open to interpretation i.e. do they include all file sizes or just file sizes over some set value. That can make a big difference.

Also there has been another big W10 update in the last day or so that will have caused significant fragmentation.

I have another question: Can daily defragmentation cause any harm to the drive? I guess probably not but I'm curious.

Hi Bicycle,

I recommend to most users that they should defrag their hard drives about once a month, but your computer might need it more frequently.

Unless you see a significant difference to your read speed once defragged then daily is probably a waste of time.