Animal trainers have this problem all the time. Animal performs behavior ‘x’ gets a reward. But the animal might have been doing other subtle behaviors at the same time, and map the reward to ‘y’. So instead of reinforcing ‘x’, you might be reinforcing ‘y’. And if ‘x’ and ‘y’ are too close for you to tell apart, then you’ll be in for a surprise when your perspective and context changes, and the difference becomes more apparent to you. And you find out that the bird was trained to peck anything that moves, instead of just the bouncy red ball or something.
Psychologists have a formal term for this but I can’t remember it, and can’t find it on the internet, I’m sorry to say.
Come to think, industry time-and-motion people suffer the same problem.
I heard a funny story once (online somewhere, but this was years ago and I can’t find it now). Anyway I think it was the psychology department at Stanford. They were having an open house, and they had set up a PD game with M&M’s as the reward. People could sit at either end of a table with a cardboard screen before them, and choose ‘D’ or ‘C’, and then have the outcome revealed and get their candy.
So this mother and daughter show up, and the grad student explained the game. Mom says to the daughter “Okay, just push ‘C’, and I’ll do the same, and we’ll get the most M&M’s. You can have some of mine after.”
So the daughter pushes ‘C’, Mom pushes ‘D’, swallows all 5 M&M’s, and with a full mouth says “Let that be a lesson! You can’t trust anybody!”