Indoor rainy day activity totally flopped

Saw this Pinterest craft about making a marble run out of paper towel tubes. Sounded easy, looked cool. My 8yo and I spent an hour on it and it was a total mess—tubes falling apart, tape everywhere, the marbles didn't even roll right. He got frustrated, I got frustrated. In the end we just built a fort out of the tubes instead lol. Sometimes the best activities are the accidents.