Trying to paint my toes and I'm struggling to get all the old color off, so I ask the hubby if it's…

Trying to paint my toes and I'm struggling to get all the old color off, so I ask the hubby if it's all off. He looks for a good amount of time and says "yeah Looks good." I rest for a few minutes, get in position to paint, grab the paint only to see 2 of my toes clearly still have the old color on them. Ugh!!