Keyboard spacebars wear out faster on the right side for the vast majority of users because human beings are overwhelmingly right-handed and unconsciously favor that thumb.

A closer look

Keyboard spacebars wear out faster on the right side for the vast majority of users because human beings are overwhelmingly right-handed and unconsciously favor that thumb. Even left-handed people often exhibit this asymmetrical wear pattern due to standardized typing classes that implicitly push the right-thumb habit on young students. If you take a close look at a well-used mechanical keyboard, you will almost always find a shiny, polished spot specifically on the right half of the longest key, leaving the left side looking relatively pristine. This tiny detail is a stark visual representation of our collective lack of ambidexterity and the sheer repetitive monotony of modern digital work. It proves that no matter how advanced and symmetrical our hardware designs become, our flawed, lopsided human biology will always find a way to slowly ruin them