After coming across the code golf trivia around the site it is obvious people try to find ways to write code and algorithms as short as the possibly can in terms of characters,
Writing "code golf" solutions are often to do with showing how "clever" you are in getting the job done in the most succinct way even at the expense of readability. Quite often, however, more verbose code including, for example, memoization of function results, can be faster. Code size can matter for performance, smaller blocks of code can fit in the L1 CPU cache but this is an extreme case of optimization and a faster algorithm will most always be better. "Code Golf" code is not like production code - always write for clarity & readability of the solution rather than terseness if anyone, including yourself, ever intend to read that code again.