Earlier quoted context omitted.
And Googles version is probably much more successful. I noticed the same with Facebook and I don't think it's very effective. Talk once about a topic or like a page and you'll see related ads for a long time. Google seems to have smarter algorithms that try to detect a trend to figure out if you're really interested in something or just mentioned it once.
Amazon is a similar offender. "Oh, you bought a fridge yesterday? How about you buy another one?"
Mind you, I am near tinfoil-level conscious of "cross contamination". I use Firefox on iOS for Facebook, and I never use it for any other browsing other than FB. My name is not my real name on FB, and it's written in a non-latin alphabet. I never discuss products on Facebook, and besides these events happen immediately after.
I have no idea how Facebook is targeting me with Amazon ads for things I just browsed on the Amazon app.