Cost to Serve

Name your most profitable customer. Now tell me how you know.

You can name your biggest. Revenue by customer is in every system you own. Margin by customer is in none of them, so the answer arrives as a feeling: they are easy, they pay on time, you like them. That is a reputation, not a number.

The other tells. Your gross margin is one blended figure for the whole business. You discounted to win something last year and never established what the discount cost. Someone asks whether to take a piece of work and the answer is instinct, delivered confidently. And the customer everyone privately dreads is still on the books, because nobody has ever put a figure on the dread.

If you cannot rank your customers by what they actually contribute, this gap is open, and every pricing decision you make is a guess wearing a suit.