hard to understand please help!

[louis1991]

i have joined recently and i have a brief idea of how to do this. i have filled out Most of the shown available offers and completed a few and have recieved some points back. this was from completing 10 offers. but my question is how come some others wont give back credit even when i filled it out?
i dont understand the full concept of filling these out can someone please help me.

thanks for reading.