system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why i don't get tired of eating the same breakfast for 365 days, but get tired immediately if i eat the same dinner 4 days in a row.
gpt
It's a matter of habit, really. 

You're used to eating the same stuff, therefore you feel more comfortable doing that. But you weren't brought up to eat the same dinner everyday, so you **want** and **prefer** the variety with that meal. Your body (really the brain) is used to that cereal, glass of milk and sandwich in the morning that you've eaten for 15 years in a row almost every day so it just goes automatically and doesn't complain about it.