Writing code that other people can read and extend, writing the least amount of code possible (as in knowing when not to solve a problem with code, not concisio

Writing code that other people can read and extend, writing the least amount of code possible (as in knowing when not to solve a problem with code, not concision), good communication with coworkers and project managers/clients, deep understanding of the problem that they're trying to solve, the ability to work quickly and with few mistakes or oversights, and lots of experience to build an intuition of what to do in any situation.