Trying to dissolve edge, but sometimes blender brings the origin to a face instead and doesn't dissolve the face. REALLY annoying! I'm trying to dissolve faces, but half the time it doesn't dissolve them but instead moves the origin to the middle of a face on my object. The same face every time. Why??
I think you are confused about how to use  dissolve..  or about the differences between dissolve and delete:

check this fast video I made for you:

https://www.youtube.com/watch?v=7vEnOqUZ7Lk



also check:

Differences between dissolve and delete?

and this: