Most owners can say what they spent last quarter. Far fewer can say what one new customer cost, and whether that number is going up. Spend sits in different places: agency retainers, ad accounts, tools, salaries, travel, and the discount given to close a deal. Nobody adds it up the same way twice. So the conversation about cost becomes a conversation about opinions, and the decision to spend more or less gets taken on nerves rather than numbers.
Why it persists. Acquisition cost sits between departments. Finance holds the invoices, marketing holds the ad accounts, sales holds the discounts, and nobody owns the whole number. The data needed to build it lives in four systems that do not agree on what a customer is. Working it out by hand takes days, so it gets done once for a board deck and never again, and by the time anyone looks at it, the figure is old.
If it stays unresolved. You keep buying growth at a price you have not checked. The business can look busy and still earn less on each customer than it did last year. The problem usually becomes visible only when a slow quarter, a price war or a funding gap removes the room you had to absorb it.