The worst old age makeup on film certainly wasn't intended to be terrible. In many instances, legendary makeup artists thought they were doing a good job, but instead put jaw-droppingly fake, rubbery foam faces onscreen. Why? Maybe they were having an off day. Or maybe it was because they got paid a ton and it's not like you make Citizen Kane every time (although Orson Welles did that one time, and it's on here).
Bad old age effects are a matter of doing the impossible even if you’re a master makeup designer. Stan Winston and his team couldn’t convince us that 19-year-old Winona Ryder was an old lady at the end of the otherwise wonderful Edward Scissorhands. And if he couldn’t do it, no one could. She's had too much youth in the eyes to fake it.
Many times, directors opt to use an old actor in place of attempting to add years by piling on makeup. See Titanic, Interstellar, etc. Would it have killed Francis Ford Coppola to get an older man to play the aged Michael Corleone in Godfather III, at the very end of the film? Al Pacino's powdery hair and pleather skin were surely an avoidable old age makeup fails.
Of course, some movie goers are fine with what others consider bad old age makeup. Chances are, you may disagree with what is deemed the worst movie makeup ever. But does anyone think Leonardo DiCaprio in J. Edgar isn’t cringeworthy?
Many of these bad old age makeup jobs won awards. So go figure.