Spammy marketing means the leadership of the company has bad product sense. No point in wasting time on that sort of product.
I understand this point-of-view.
But this cannot be the sole reason. Are there any other reasons that are concrete, provable?
And this is also not a universal statement. I have seen good products, not limited to software industry, that were excellent, but the marketing was spammy.
With Pocket in particular, the bundling with Firefox moved my impression of it from "this is a potentially useful tool" to "this company feels like they need to force their product down my throat by bundling it with a browser - I don't know why they're doing that but it makes me not want to keep any data with them"