I see it constantly. A business spends £500 a month on Google Ads, gets a handful of clicks, and nothing converts. They assume Google Ads doesn't work for their industry. Usually, the problem is the setup — not the platform.
The most common issue is keyword match types. When you use broad match keywords, Google shows your ad for searches that have nothing to do with your business. A plumber bidding on 'pipe' might appear for 'pipe band' or 'pipe tobacco'. Every one of those clicks costs money and produces nothing.
Negative keywords are the second failure point. These are the searches you explicitly don't want your ads to appear for. Without a properly maintained negative keyword list, you'll keep bleeding budget on irrelevant traffic. I build and actively update a negative keyword list for every account I manage — across all plans, from day one.
Then there's the landing page problem. Sending ad traffic to your homepage is almost always a mistake. A homepage is designed for many audiences. Someone who clicked an ad expecting a specific solution needs a page that answers exactly what the ad promised.
Finally, and critically, no conversion tracking. If you don't know which clicks turned into enquiries or sales, you're making budget decisions based on guesswork. The data is there — it just needs to be collected properly and read clearly.