What causes these holes in my husbands t-shirts?

Solution:
Air-dry t-shirts whenever possible to preserve their integrity.
If using a dryer, select a low-heat or delicate setting.
Avoid overloading the dryer to minimize friction.
4. Moths or Pests
Cause: Tiny holes (often in clusters) could be caused by moths or other fabric-eating pests. These insects feed on natural fibers like cotton, wool, or linen.
Solution:
Store clothing in sealed containers or garment bags.
Use cedar balls, lavender sachets, or moth repellents in your closet.
Inspect clothing regularly for signs of pest damage.
5. Abrasion from Rough Surfaces
Cause: Frequent contact with rough surfaces (like countertops, desks, or car seats) can wear down fabric over time, especially thinner materials.
Solution:
Avoid leaning or resting elbows on abrasive surfaces while wearing t-shirts.
Opt for thicker, more durable fabrics if this is a recurring issue.