The summary.
THE MOMENT-TO-MOMENT ACTIVITY IS THE GAME; EVERYTHING ELSE DECORATES IT
Build that first, as grey boxes with no art or menus. If it is not enjoyable there, content will not save it.
EVERY UPDATE MUST USE ELAPSED TIME
Otherwise movement speed depends on frame rate and the game behaves differently on every machine. Use a fixed timestep for anything requiring determinism, with a cap on updates per frame.
Measure frame time, not frame rate — it is linear and reveals the variance an average conceals.
A PROTOTYPE ANSWERS ONE QUESTION AND IS THEN DISCARDED
Keep the knowledge, not the code. Effort invested creates attachment, which is exactly what must be resisted.
SCOPE EXCEEDING WHAT THE TEAM CAN FINISH IS THE COMMONEST FAILURE
Finishing takes roughly as long again as reaching a playable state, and most of that work is not the interesting part.
FINISH SMALL GAMES BEFORE STARTING LARGE ONES
Completion teaches polish, menus, saving and builds — the final fifth, where most projects die.
BINARY ASSETS CANNOT BE MERGED
Use locking, or simultaneous edits lose someone's work.
