Google Ads mistakes that burn your budget (and how to fix them)

Google Ads doesn't throw money away on its own: it spends it exactly the way you tell it to. The problem is that many of the options pre-selected when you create a campaign are designed to spend the full budget, not to bring you customers. It doesn't matter whether your business is in Mexico City, Monterrey, Guadalajara or Mérida: when we review accounts that aren't delivering, we find the same mistakes almost every time. The good news is that every one of them is visible inside the account, and most can be fixed in an afternoon.

Targeting mistakes: paying for people who won't buy

1. Using broad match without conversions or negative keywords

According to Google Ads Help on keyword match options, broad match shows your ad on searches related to your keyword even if they don't contain it, and it's the default option. Google recommends pairing it with automated bidding, because that's where the system learns from your conversions which searches actually sell. Without well-measured conversions, that learning doesn't happen: broad match simply opens the door to thousands of vaguely similar searches. If your account is new or doesn't measure contacts, start with phrase and exact match, which give you more control, and open up broad match only once you have data.

2. Not reviewing the search terms report

Your keyword isn't what people typed. The search terms report shows the real searches that triggered your ad, and from there you can add the irrelevant ones as negatives. An accounting firm in Monterrey bidding on "contador" (accountant) will find "calorie counter", "accountant jobs" and "accounting course" in there. Watch one detail about negative keywords: they don't exclude close variants, so singular, plural and synonyms have to be added by hand. Every useless search you don't block, you pay for again next week.

3. Leaving location set to "presence or interest"

In advanced location options, the default is "presence or interest": your ad reaches people who are in your area or visit it often, but also people who have merely shown interest in it. That makes sense for a hotel or a real estate agency selling to buyers from other cities. For a repair shop, a clinic or an at-home service in Guadalajara, someone searching from another state usually isn't useful. In those cases switch to "presence", which limits ads to people who are, or regularly are, in your locations. Google warns you'll get fewer impressions; that's exactly the point.

4. Advertising at hours when nobody answers

By default, campaigns run all day. With ad scheduling you choose the days and hours your ad can show, or raise and lower bids by time slot. If your contacts arrive by phone or WhatsApp and nobody replies at 11 p.m., that click becomes a customer who messages your competitor the next morning. First look at when your contacts come in, then trim.

Measurement mistakes: Google optimizes blind

5. Not measuring conversions, or measuring the wrong ones

This is the most expensive mistake because it drags all the others along. Without conversions, you don't know which campaign brings customers, and neither does Google. The opposite case is just as harmful: counting every visit to the contact page as a conversion, or measuring the same action twice (once with the Google Ads tag and once imported from Analytics), inflates the numbers and teaches Google to find browsers. A conversion should be a real contact: a submitted form, a call above a minimum length or a click to WhatsApp. If you're not sure how to set that up, here's how to track WhatsApp, call and form conversions.

6. Launching Performance Max before you have data

Performance Max campaigns spread your budget across YouTube, Display, Search, Discover, Gmail and Maps, and bid according to your conversion goals. They work when those goals are well measured and there's volume. Launch one on a new account or with poorly configured conversions and the system optimizes toward whatever it can count, which tends to be the cheapest thing, while you get less visibility into which searches or sites the money went to. For almost any service business, the first campaign should be Search.

Ad and landing page mistakes

7. Sending every ad to the home page

If someone searches for "dental implants in Mexico City" and lands on your clinic's home page, they have to guess where to click. Each keyword's Quality Score is rated from 1 to 10 on three components: expected click-through rate, ad relevance and landing page experience. Google clarifies it isn't an input to the auction but a diagnostic; still, what it measures, whether your ad and page answer the search, does affect what you pay and how many of those clicks contact you. Each advertised service deserves its own page, fast on mobile and carrying the same message as the ad.

8. Accepting recommendations without reading them

The recommendations tab suggests raising budget, adding broad match keywords or turning on other networks. Some are useful; others just widen spend. Review them one by one and turn off auto-apply for the ones you don't want Google to execute without asking. It's also worth checking whether your Search campaign has the Display Network or search partners turned on, and deciding whether you really want them.

A 30-minute weekly review

1. Open the search terms report for the last seven days and add the searches that don't sell as negatives.
2. Check that every conversion is still recording data and that there are no odd spikes pointing to a duplicated tag.
3. Compare cost per contact across campaigns and ad groups; shift budget toward the ones bringing cheaper contacts.
4. Look at the locations column: if cities you don't serve show up, review the presence setting.
5. Read new recommendations and decide which to apply yourself, not the account.

If you're only about to open your account, these mistakes can be avoided from day one. Our guide to Google Ads for SMBs in Mexico explains how to build a small first campaign that's measurable and easy to correct.

Why does my Google Ads campaign spend money but bring no customers?

Almost always because of a mix of three things: searches that are too open and bring clicks from people looking for something else, conversions that aren't set up or measure the wrong thing, and a landing page that doesn't answer what the person searched for. The search terms report and your conversion settings tell you which of the three weighs most.

How often should I review search terms?

On a new account, every week. Once the negative keyword list is mature, every two weeks is usually enough, unless you add new keywords or switch to broad match.

Should a service business use Performance Max?

It can work once the account measures its contacts well and has conversion volume. To start, a Search campaign gives you more control over which searches show your ad and how much you pay for each.

If you'd rather have someone review your account with you, that's what we do as a Google Ads agency: we start with measurement, clean up search terms every week and report what each contact cost. And if you want to understand how much you should invest, read how much Google Ads costs in Mexico.