Windows 95 let installers trash its files then fixed the mess behind their backs
(www.theregister.com)
Defragging monthly, fixing registry values and hoping windows 98 would fix things this time was all I remember about Win95.
But windows 98 came out about 3 months after I built my own first PC. It was still full of problems, but I eventually ended up ok NT/2000 and things got better. Then I quit windows for good when apple went to Intel.