How accurate is the assessment of sites like calculate site worth, Alexa Traffic etc?

Question

Project management

Worthofweb example, we give a link to the site, it uses public APIs like Alexa Traffic Rank & charts etc and based on this data gives indicators of the "possible" income of the site.
But I was always confused by the numbers, both Alexa Traffic and all calculators.
Asking customers this is somehow inconvenient.
Also, in addition to income, traffic.
How accurate are Alexa metrics?
Question to those who have their own website with income.

Answer 1

How accurate are Alexa metrics?

Quite accurate, there are many methods, from listening to dns, to buying analytics data.

and on the basis of these data gives indicators of the "possible" income of the site.

this is such a thing, that is, if you decorate the site with banners of sponsors, adsense, sell articles and, in short, squeeze the maximum out of the site's theme. In real life, everything depends on such factors that cannot be taken into account automatically, misses can be orders of magnitude in both directions, because you can also sell yourself in very different ways. We can only talk about + - getting into one segment of monetization, for example adsense - stupid traffic * ktr * cost per click.