The scenic route needs no defence
The shortest route measures distance, not everything you might value about getting somewhere. If you have the time, you can choose the street with the old balconies and the corner bakery simply because arriving is only one part of the walk you are taking.
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What the route contains
Two streets may lead to the same station. One is quicker. The other passes a row of interesting shop windows and a small square where you like to pause.
Efficiency is one quality of a route, not its entire description. When timing permits, choosing the longer walk can be a direct expression of what you enjoy rather than a failure to choose sensibly.
The practical condition matters: missing an important train would change the choice. On an open afternoon, however, a few additional minutes may be exactly what you want from the outing.
Decide what this particular trip is for. If it is only transportation, take the direct street. If the walk itself is part of the pleasure, include something along the way that makes you glad to be outside.