Amazon ads live or die on search volume. Without people searching for a keyword, your bid doesn't matter. Broad match campaigns catch related searches you'd otherwise miss, multiplying your chances at impressions and sales.
When it comes to Amazon, it's search volume driven. So if people aren't searching up your keyword, it doesn't matter how much you bid, you just won't get any sales. This is why I'm a big fan of running broad match campaigns, mostly because not only are you getting your targeted keyword that you're trying to get sales for, you're also going to go— you're also going to go ahead and get low-hanging fruit, other keywords you wouldn't you'll be able to actually target and convert on. So again, if there is no search volume, you can't expect to get any type of impression. If you can't get impressions, you can't get sales.
