Ya know why it takes 500,000 sperm to fertlize one egg?
Being male, they will not read the directions.
MOST gun makers have instructions for the maintenance of what they make. Their are some points (and climates) for light oil. Some points for grease. Depends on WHAT gun, what part, what climate. Firearms we used in the interior of Alaska in January had very little lube at all. M1 Garands call for grease at several points.
No one answer. I did use a light bit of white lithium on the rails of my 1911s (before that horrible boating accident)