Why Most Google Ads Accounts Leak Money
The structural failure in most accounts is that they were built around what the business sells rather than around how people buy. Service lines with very different margins share one budget. Research queries and ready-to-hire queries sit in the same ad group competing for the same bid. When a cheap, high-volume term dominates impression share, it starves the terms that actually produce booked work, and the account keeps reporting a respectable cost per conversion while the pipeline gets worse.
Quality Score compounds the problem. Google calculates it from expected clickthrough rate, ad relevance and landing page experience, and it feeds directly into what you pay per click and whether your ad shows at all. Generic ad copy pointed at a generic page is not only a conversion problem. It is a pricing problem, because you are bidding against competitors whose relevance is subsidizing their cost per click while yours inflates it.
Then there is the search terms report, which almost nobody reviews at the cadence broad match demands. Automated match types and Performance Max will find query space you never intended to buy. Some of it is valuable and deserves promotion into its own campaign with its own budget. Most of it is not, and it only leaves the account when someone deliberately sculpts it out with negatives. That review is a standing weekly job, not a quarterly clean-up.