You already know it isn't a traffic problem.
Most people running a store never get that far. Here is what it usually turns out to be instead.
Customers vanish in the checkout. 68% of carts get abandoned. Most of the reasons are fixable. Most stores never find them.
More traffic. Same revenue. Ad spend keeps climbing. Conversion hasn't moved in two years. The problem was never traffic.
You keep having the same meeting. Someone wants the hero image bigger. Someone else wants the button green. Nobody has evidence, so the loudest person wins and the number stays where it is.
You've had an audit before.
It was sixty pages, it arrived as a PDF, and nobody opened it twice. I know the format. I have been handed a few of them myself.
So this one arrives as a recording you will actually watch, and a list your developer can start on Monday. If it isn't useful, you don't pay. That has never happened, but the offer stands.
Philip Wallage 
