Photos got rejected on shutterstock are there any better alternatives to the website

Hello everyone I just made a Shutterstock contrib account and tried uploading some photos on my phone as they arent the best quality but I thought they would be good test subjects to see how much I make before I put my real project out there which is a twitch emote I made called bupchamp.

My main question is what stock platform provides the best passive income and why do my test photos get rejected on shutterstock because they are slightly grainy or other reasons. I want something hassle free but will allow me to make money off my bupchamp emote.