How many cards should you pull in a tarot reading?

I'm curious to know, in the realm of tarot readings, how many cards should one ideally pull to gain a comprehensive yet concise understanding of a given situation or question? Is there a universal rule of thumb, or does it vary depending on the reader's style, the specific question at hand, or perhaps even the intuition of the moment? And what factors might influence the decision to pull more or fewer cards during a reading?