After Hotosm changes uploaded, satellite image changes

I was editing via Hotosm. I found to find the outline of the buildings, the image was too dark. I couldn’t even see the cross hairs to know where I was clicking. I added a few buildings and then saved and uploaded. I then went back to editing and suddenly the image was bright and clear, I could actually see the buildings. What happened? How do I always get that good image. I am not sure how to explain what else I did that made a difference, I am a newbie.