I can't say how many times I heard my mother say that.
When I was growing up, we never had a car so, we always took the subway. My mother always reminded us to read the signs before we got on any train.
I should have taken that advice this morning. I washed my hair using a new shampoo which comes in a tube, the same as the conditioner. I did my usual wash and rinsed the shampoo out. I then picked up the conditioner and applied it to my hair. When I was combing it through I was surprised to see that it seemed to be foaming. As I rinsed it out, I noticed that my hair felt very different. It seemed very coarse and knotted. I couldn't understand it.
Then I looked at the tube. I had used shampoo for a second time. Once I found the conditioner my hair felt much better. It was smooth and not coarse. Problem solved.
I guess I should be more careful when showering and read the names on the products I use. Mother knew best, "Read the signs".