Having no particular pattern, purpose, organization, or structure
The ones that do tend to be hit-or-miss.
The sites, admittedly, can be hit-or-miss; many are simply banner farms with a few low-quality images that no one would use combined with key words that lure in unsuspecting viewers.
Checking the site is sometimes a hit-or-miss proposition, but with the handy "Fly View" button you can quickly see if the shirt you like is in the size you want.
hit-or-miss, hopeful approach.