Yeah that happens often. I ran these campaigns for two years - you effectively get 200 dials, knobs, and levers to pull all making minor changes to an incredibly complicated adtech ecosystem. My first year I ran 80 of these campaigns, and could spend <20 minutes a week on each.
Missing something like “exclude recent purchasers” was easy to forget, but easier to not even have time to set up. (It might take 10-30 minutes to set that up)
I've noticed a lot of Instagram ads where the advertisers seemed to ignore a regional target, or Instagram does. I get ads for restaurants all over the country, which makes no sense for the advertiser. I'm not about to go eat at some Mexican restaurant 2000 miles away from me in a suburb.
Missing something like “exclude recent purchasers” was easy to forget, but easier to not even have time to set up. (It might take 10-30 minutes to set that up)