Personally, I think it's more about balancing trade offs. You need to have some semblance of target performance needs. Bad architecture can be hard to overcome

Personally, I think it's more about balancing trade offs. You need to have some semblance of target performance needs. Bad architecture can be hard to overcome later. Most decisions are small, but can lead to compounding effects. Personally, I think one should also avoid premature pessimissation as well. No one in their right mind would use bubble sort over quick sort, for instance (not saying quick sort is the best algorithm, but it's better than bubble sort). One pet peeve I have in C++ is when I see people initializing a std::string with a literal empty string instead of using the default constructor. The default constructor is usually a memset or initializing 3 pointers. Initializing with an empty literal involves a call to strlen, malloc and strcpy. I've yet to see a compiler optimize this. May not seem like a big deal, but considering one of the most frequently used data types is a string, it adds up a lot. Most of the applications I've worked on show std::string methods and constructors as hotspots when profiled (back office financial systems). I agree one should avoid premature micro-optimization, but that you can also avoid premature pessimissation.