But it didn't work in the sense of making me buy more games. I had hundreds of copied games and a couple dozen purchased ones, and if copy protection had been perfect, I would have had a couple dozen. The publishers always acted like I would have purchased the hundreds, which was impossible.
So it was really a competition between the publishers to out-protect the others more than between the publishers and the customers.
You take a floppy disk, use a pin to make a hole on the magnetic medium at a random place, then format the disk so that sector is marked as a "bad sector". You hardcode the sector ID in your app, then when your app runs, you try low-level formatting that sector. If it can be formatted, it's a pirate copy.
Floppy disks had physical read-only mode, so my app asked users to put their disks in read-write mode to work :)
http://dmweb.free.fr/community/documentation/copy-protection...
Nearly 40 years later, I still wouldn't call it "wasted time".
The software itself was impressive, a full-featured word processor with an 80 column display.