Pay-per-click advertising places the business in results and charges when someone clicks.
The vocabulary
Impressions — times the advertisement was shown.
Clicks — times it was followed.
Click-through rate — clicks divided by impressions. A low rate usually means the advertisement is reaching the wrong people or saying the wrong thing.
Cost per click — what each click costs, set by auction against competitors bidding on the same terms.
Conversion — a click that became an enquiry. This is the one that matters; the rest describe traffic.
Why clicks are not the measure
A click is a visitor, not a customer. The chain is impression, click, enquiry, job — and money is lost at every step.
The figures that decide whether it works are cost per lead and, ultimately, return on ad spend read against margin rather than revenue.
Where the money is wasted
Terms that are not buying intent. Someone searching how to fix something themselves is not a customer.
No negative terms, so the advertisement shows for "free", "jobs", "DIY" and similar.
Sending everyone to the home page rather than a page about the thing they searched for.
No geographic limit, paying for clicks outside the service area — see travel charges.
Running outside hours nobody answers. An urgent search at ten at night that reaches an unanswered phone is a paid click and a lost job.
Against unpaid search
It starts immediately and stops immediately. Search engine optimisation is slower to start and keeps working.
Most established local businesses use paid advertising to fill gaps rather than as the base.
Judging it
Over enough volume to mean anything. A handful of clicks says nothing, and decisions taken on a week of data are usually reversed a week later.