Check if a flight deal is good.
A headline fare only tells you whether a deal is good if it includes everything. Unbundled carriers strip baggage and seat selection out of the fare precisely so the search result looks cheap, and adding them back routinely moves a fare by 20 percent — enough to reverse the ranking between two options. Comparing that all-in figure against the route's typical fare gives the real verdict. The time penalty is shown separately because it is a judgement rather than a cash cost: each connection adds roughly two and a half hours of layover, boarding and extra risk, and pricing that at your own hourly value shows when a cheap connecting fare is not actually cheap.
All-in cash cost
All-in = quoted fare + baggage fees + seat and extras
Time-adjusted cost
True cost = all-in + connections x 2.5 h x your hourly value
Because the cheapest fare on record is usually an error fare or a flash sale on inconvenient dates, and it is not a target you can plan around. The route's typical level is what you can realistically expect, so it is the right benchmark for judging whether to book now.
It makes an implicit trade-off explicit. You are already deciding whether four hours of layover is worth 90 in savings; naming your hourly value just makes that consistent across bookings. Set it low if you enjoy travelling and high if the time comes out of work or family.