Routine - does it ensure doing in safe manner

I was out of station for two days and stayed in a rented space. 

To brush my teeth, confident of items in the regularly used kit, I picked up a brush and tube with paste. 

Opened the tube and got strong smell of body ache pain relief ointment. Good that I didn't apply on the brush or put in the mouth.

Realisation came to me that overconfidence is not good. Familiarisation breeds to complacency and taking things lightly.