- Anything that hints at the fact your looking for a product is dominated by the products themselves whereas a lot of the times you want unbiased advice, eg which category of product should I buy. Comparison sites themselves are very untrustworthy (for the most part)
- If your "learning" something (eg guitar, weight lifting, random hobby, programming) its usually a year or so in before you know the best resources to learn with. However insights like this aren't easy to find so everyone goes through the motions
- Again if your learning something the material is not split between "depth" levels. Eg the resources needed for learning about "black holes" for a layperson VS someone with a strong interest in space VS a physicist are different. As are news etc.
PS An improvement in search is badly needed, good luck with your project.