When I was a little girl, my father taught me the Golden Rule: do unto others as you would have them do unto you. The message I got was that I need to treat others with the care and consideration that I want and that I have a responsibility to act in ways that take into account the well-being of others.
And that's why we need to wear face coverings during this pandemic.
Wearing a face covering doesn't protect me that much (although it's better than nothing). But if I wear one, it protects you. If you wear one, it protects me. And if we both wear one, the virus is much less likely to infect either of us.