Threes
There is symmetry in threes. Our brains like to think in threes, because it is a pattern: three is the lowest figure that can be used to form patterns in our mind. A good Venn diagram can demonstrate the value of three.
It happens elsewhere too – in triathlons, in the three acts in a play, or setting up for photography, trilogies in film, in making a point, in categorising, clustering, or organising.
Three golden threes that I like to keep on top of, for any project or goal, are:
Project management triad: Cost/Scope/Schedule
Productivity triad: People/Process/Tools
Professional excellence triad: Risk/Quality/Competence