First, I'll admit straight out that I didn't search for this answer before posting (I came back and added this sentence after I typed the below)

I have a merchant with a 2600 product datafeed that some of the products return a Red X where the image should be in the preview. I've checked the links, and they are correct (save a handful).

I've noted that if I sit around long enough, they mostly all show up.

Is this common in a situation like this? The merchant site is responsive when you're navigating it, so it just the strain of pulling 200 pictures at a time?

Is that a concern we should have with the website architecture in general?