practiced system design by redesigning the food delivery app on my phone instead of studying flashcards and it stuck way better

Flashcards taught me vocabulary, load balancer, cache, sharding, but I couldn't string them into an actual answer under pressure. Picking an app I use daily and asking how I'd actually build it forced me to make real tradeoffs instead of reciting a checklist. Failed my first two attempts at it out loud before it clicked.