It’s not rocket science:
1. You can’t breathe easily through common mask fabric, so you inhale and exhale around the edges of the mask. (That’s why glasses fog up.) Thus, the same germs that you might sneeze out are being steadily breathed out into whatever space you are sharing.
2. The fabric itself is too coarse to trap viruses. Anyone disputing this can try to prove me wrong by breathing air exhaled by an Ebola victim that is filtered only by common mask fabric. But first update your will.
3. Because you cannot easily breathe through the fabric, your body has to work harder to obtain given amounts of oxygen, and you are inhaling some stale mask air as you breathe. People can get used to this, just as they can get used to working in 100 degree heat; but the body is still having to work harder to get oxygen.
Who cares.
Try these fabric masks plus the welders plexi glass covering at same time. Harris County elections are run by Dems now plus plastic gloves all part of required wearing for election workers. 14 hour a day shift for ten days.