I've been a beauty editor for four years and the single question I'm asked at every dinner party I attend is the same: 'what's the one product I should buy?' The first time I was asked, I said something useful. The hundredth time, I started to dread it.
The reason it's a hard question is that the honest answer ('it depends on what you want, what your skin does, what you've already tried') is exactly the answer the asker doesn't want to hear. They want a recommendation. They want me to skip the calibration and tell them the thing.
After enough repetitions I now have a stock answer for each of the categories: skincare (start with The Ordinary Niacinamide and SPF, in that order), makeup (NARS Radiant Creamy Concealer, even if you skip foundation), hair (Olaplex No.3 if you've ever coloured), tan (Loving Tan 2HR Express if you've ever tanned, Eco Tan Winter Skin if not).
The stock answers are not lying. They are the products I genuinely use, the products our database genuinely scores highest, and the products that genuinely solve the most common version of the dinner-party question. They are not the right answer for everyone. They are the right answer for the median person asking.