---
title: 2220 Product The Bathtub Problem
description: "## The Demand Tomorrow, run the math on your own drain. Calculate what your current Guest attrition is actually costing you in a year, using Reichheld's numbers as your baseline: a 5% increase in retention can lift profits 25 to…"
url: "https://kb.jeffreysummers.com/docs/2220-product-the-bathtub-problem/"
updated: "2026-08-03"
category: Product / Product Fieldbook
---

# 2220 Product The Bathtub Problem

## The Demand

Tomorrow, run the math on your own drain. Calculate what your current Guest attrition is actually costing you in a year, using Reichheld's numbers as your baseline: a 5% increase in retention can lift profits 25 to 95%, and a new Guest costs 5 to 25 times more to acquire than an existing one costs to keep. Decide whether your next marketing dollar goes to the faucet or the drain.

## The Work

Your current repeat visit rate, as a stand-in for how open your drain is:

Your current marketing budget allocation — estimate the split between acquisition (faucet) and retention (seal):

Using the 5-to-25x acquisition cost multiple, what does one lost Guest actually cost you to replace:

What have you been spending on ads, promotions, and deals in the last quarter — the faucet spend:

What have you spent, in the same period, specifically on strengthening relationships with Guests already choosing you — the seal:

Faucet or drain — where does your next marketing dollar go, and why:

The one action you will take this week to start closing the drain before you turn up the faucet: