Google is the master of wasting your advertising budget and broad matched keywords are the culprit. But do they have a purpose and should your company spend money on broad keywords?
The answer is YES in many ways. First, broad keywords can be much cheaper compared to the same keyword that is phrase or exact matched. But they also bring in a lot of irrelevant keywords. So your negative list has to be extensive for the broad keyword to work.
On average 97% of your keywords bring clicks that do not purchase. Only 3% of your keywords bring paying customers. So broad match the 3% and make sure your negative list has about 100 negatives for every 1 word you want to target.
Next major reason to keep broad keywords is they help you discover which keywords you should be targeting and are not.
Another reason broad words are effective is they help with content ideation, especially for top of the funnel words.