A mentor from the right field beats a famous one from the wrong field

The key word is “applicable.” Kyle Bragger, who founded Forrst, an online community where designers and developers shared work for critique, is not recommending mentorship in general. He is recommending someone who has worked in the particular field a founder is about to enter.

The difference matters because most expensive mistakes are local. A successful software founder can offer sensible advice on hiring and fundraising to someone opening a restaurant. The same person will not know that the lease terms decide most of the outcome, or which suppliers pay late, or which months are slow. Someone who has run a restaurant knows these things without thinking about them, and a single conversation can save a year of learning.

The condition at the end of the sentence matters too. A mentor is most useful when the founder is unsure what they are looking for, because that is when they cannot yet tell good advice from bad. Once a founder knows the field, general sounding boards become more useful than specialists.

There are two ways the advice goes wrong. The first is age. A mentor whose experience in the field is fifteen years old may be passing on rules that no longer apply, and in fast-moving trades that can do real harm. The second is dependence. A mentor who is consulted on every decision stops being a guide and becomes a substitute for judgment, and the founder never builds their own.

Finding the right person is usually easier than founders expect. People who have spent a decade in a trade are often glad to talk about it, especially when the questions are specific and the conversation is short. A request for an hour to ask about supplier contracts gets a better response than a request to be someone’s mentor.

A good arrangement is narrow and time-bound: specific questions, asked of someone who did the work recently, until the founder no longer needs to ask.