I had stage fright when I first presented the pink tower to a student under the watchful eyes of our directress. When presenting the sensorial equipment you had to make sure you did the presentation without correcting any movements or placement of the material. If you slightly corrected a block on the pink tower that was off center I was told a preschool child would copy my movements and do the exercise incorrectly. I would practice endlessly to make sure I could do the presentations perfectly.
With my own children I was much more at ease when presenting the material at home. In fact, if I made a mistake I would tell my child I did something wrong. I was pleasantly surprised when my children did the exercises correctly even after I made a mistake.
I think that perfectionism can be a stumbling block to parents and teachers using the Montessori method. We need to do our best when presenting lessons, but we don’t need to be so perfect that we can’t make a mistake.