Documentaries occasionally give a glimpse into the multitrack tapes of classic recordings.

It's not unusual for the singer's track, when heard solo in isolation away from the instruments,
to sound cack...

But mixed into the full song, it sounds perfect for the arrangement and audio mix...

I have a high tolerance for singers who aren't very good,
depending on how much I enjoy the 'feel' of a recording of a song and performance...

Perfection can be emotionally sterile...