These weights and ratings are invented to demonstrate the arithmetic and are not benchmarks.
A buyer sets four criteria with weights totalling one hundred: fit with existing systems 35, total cost over three years 25, implementation effort 25, and supplier support 15. Each option is rated out of five on each criterion.
A supplier is rated 4 on fit, 3 on cost, 5 on implementation effort, and 4 on support. The weighted total is (35 × 4) + (25 × 3) + (25 × 5) + (15 × 4) = 140 + 75 + 125 + 60 = 400. Dividing by the maximum rating of 5 normalises this to 80 out of 100.
Note what the arithmetic reveals. This supplier is the most expensive of the options and still scores well, because implementation effort carries the same weight as cost and they are rated highest on it. A seller who knew only that price mattered would have discounted unnecessarily. A seller who knew the weights would have spent the conversation on implementation, which is exactly where their advantage lay.