It is forever baffling to me that so many devs don’t seem to appreciate that small performance issues compound, especially when they’re in a hot path, and have dependent calls.

Databases in particular, since that’s my job. “This query runs in 2 msec, it’s fast enough.” OK, but it gets called 10x per flow because the ORM is absurdly stupid; if you cut it down by 500 microseconds, you’d save 5 msec. Or if you’d make the ORM behave, you could save 18 msec, plus the RTT for each query you neglected to account for.