The Google Ads audit: where wasted spend hides

Google Ads is a machine that will happily spend whatever you give it. The interface celebrates activity — impressions up, clicks up, "optimisation score" 87% — while quietly avoiding the only question that matters: how much did each real enquiry or sale cost, and is that sustainable?

An audit is just a structured hunt for the gap between what you're paying for and what you meant to pay for. In most accounts under $20k/month that gap is 15–40% of spend. Here's where it hides.

Hiding place #1: search terms you never intended to buy

The keywords you chose are not the searches you're buying. Google's "broad match" and even "phrase match" stretch your keywords to loosely related searches — a Sydney conveyancer bidding on "property lawyer" can end up paying for "free legal advice property dispute". The Search Terms report shows what you actually bought. Read three months of it. Most account owners never have, and the first read is usually expensive and enlightening.

The fix is boring and powerful: negative keywords, added weekly, forever. An account without a growing negative list is an account leaking money.

Hiding place #2: conversion tracking that lies

This is the big one, because it corrupts everything else. Google's bidding algorithms optimise toward whatever you call a conversion. If that's "visited the contact page" instead of "actually enquired", the machine gets very good at delivering window-shoppers. If conversions double-count (button click and thank-you page), the machine believes ads are twice as effective as they are — and bids accordingly.

Check: do your Google Ads conversions roughly match the enquiries in your inbox over the same month? If they're more than ~15% apart, stop optimising and start auditing — a tracking problem makes every other change a guess. This is exactly what a GA4 audit pins down.

Hiding place #3: campaign structure fighting itself

• One campaign, one theme. When "emergency plumbing" and "bathroom renovations" share a campaign, they share a budget — and the cheap clicks starve the valuable ones.
• Your own campaigns bidding against each other. Overlapping keywords across campaigns means you're your own competition at auction.
• Display and Search mixed together. The default "Search Network with Display Expansion" quietly spends search budget on banner placements with a fraction of the intent.

Hiding place #4: geography and schedule defaults

Two default settings cost Australian advertisers real money. Location settings often include people merely "interested in" your area — which is how a Parramatta dentist buys clicks from overseas. And ads running 24/7 with no schedule adjustments means paying full price at 3am for clicks that never convert. Both reports (locations, hour-of-day) take five minutes to read and routinely reveal double-digit waste.

Hiding place #5: paying for clicks your SEO already earns

Brand terms are the cheapest clicks you'll ever buy — but if you rank #1 organically and no competitor bids on your name, some of that budget buys visits you'd have received free. The answer isn't always "stop" (brand ads defend against competitors and control the message); it's knowing what share of your "great" results is just your own reputation being resold to you. Blended numbers hide this; separated brand/non-brand reporting exposes it.

The order to fix things

Tracking first — until conversions are true, everything else is guesswork. Then search terms and negatives (fastest savings), then structure, then the defaults. Expect the audit itself to be the cheapest part of the exercise; it typically finds its own cost several times over in the first quarter.

It's also the natural companion to how we run paid media: campaigns built around intent, budgets following the signal — and instrumentation set up before the spend starts, not after it's wasted.