... adding a SOURCE is a matter of quality and respect for the original author or designer.

I'm always happy to see a source right next to quotes and media like pictures or video clips. It's a matter of quality and respect for the author or designer. Think about it :)
Here's an example of how it should be done:
https://steemit.com/steemit/@hitmeasap/be-you-and-do-what-you-can-something-is-better-than-nothing-and-i-will-prove-it