Notes

The bullet-journal habit that became Producktive: coloring each day black, blue, green, or red until I could see whether it was a productive day or just a busy one.

The flywheel is the most over-claimed metaphor in pitch decks. Three tests separate a real one from a growth story wearing a costume.

What SNR means, why the metaphor spread from engineering into data, writing, and product work.

Cagan's value/usability/feasibility/viability list is easy to memorize — the point is the ordering and the timing.

A working PM's guide to root-cause analysis: the ordered sequence of cheap checks — definition, instrumentation, shape, concentration and mix — that must come up empty before the expensive funnel teardown earns its place.