Try doing that with a dodgy jack socket that meant you had to apply precisely the right pressure to the plug for the entire loading process, otherwise it would crash when it was done and you couldn't tell until it was finished. You had to breathe really gently so as not to move it for however many minutes it took.

From memory I could successfully load from and use about half the tapes I ever bought for my speccy, and I still don't know whether it was me or them.

Worth it, though.