So hypothetically if you have a very busy person who is mobbed by a lot of cold pitches, they might have a bit of pitch fatigue and assume that anybody cold pitching them is likely about as good a fit as the average cold pitcher, which is to say "total waste of my time." That very busy, selective individual probably has friends who are less mobbed by pitchers. Those friends might even be flattered to hear from you. Pitch them, with the goal of convincing them your startup/story/invitation to dinner and a movie/etc is so attractive that it is worth giving a warm intro to their friend. A warm intro in the Valley appears to be frequently a short two-sentence email: this is how I know X, here's why he's valuable to you, you guys take it from here.

This is how the real world works, over and over again.