If you own physical discs, you can verify them against the Redump database. If your childhood copy of Crash Bandicoot no longer matches the hash, your disc is literally rotting away (disc rot). You can know to back it up now before it becomes a coaster.
The project uses specialized software and methodologies to extract every bit of data from a disc, including technical metadata that standard ripping tools often miss. Verify your PSX/PS1 discs before posting what is redump