Energy is one of the easiest places to waste money through repeated manual decisions. When to charge the car, when to heat, what can run at the same time, and what should wait are all decisions most people make repeatedly — or not at all.
In a better system, charging can start exactly when the cheapest tariff window begins, run at full usable capacity, and stop cleanly when that window ends — without manual scheduling. That is not just convenience. It is coordinated, repeatable behaviour.