The problem was that again the staff members made incorrect assumptions based on what they were looking at.

Did he and players throughout the league make incorrect assumptions?

This is an incorrect assumption as it was set up specifically by the government of the day not to be a trade union.

"Usually, the clerk would make the incorrect assumption and give me the rate since I knew enough to ask for it."

Many players play under the incorrect assumption that poker is a game of luck.

Without this level of recognition incorrect assumptions will be made about the words.

Many structural problems in the model come from poor or incorrect assumptions.

I think this incorrect assumption explains the basis of your question/confusion.

The incorrect assumption had to come after the pregnancy ended.

You've made the incorrect assumption that politicians are good leaders.