>>2478312>Boot outsoles are generally harder, thicker, longer wearing but also less grippy for that reason.They usually have the right amount of grip and sole stiffness for the terrain they were designed for. Trailrunners do not have better grip just because they are softer. That's a marketing lie and I recommend you test it out yourself before deciding to go into the mountains in potentially wet conditions with something like a trailrunner.
There is a lot that goes into optimal traction:
>Midsole StiffnessIn some terrain you need a stiff midsole for optimal traction (rocks), in other terrain its the opposite (ice), and then there is terrain where it doesnt matter too much (wet bog).
>Midsole Hardness softer (EVA, cardboard, air) = less durable, more comfortable
harder (Nylon, PU, Leather) = more durable, usually also stiffer
>Rubber/Outsole HardnessVibram generally produces outsoles with the maximum hardness they can get away with for the intended terrain - for maximum thread pattern durability - without sacrificing optimal traction. Soft outsoles are a chinese thing for cost reduction and comfort, except on ice.
>Rubber/Outsole MaterialThe actual rubber material used is crucial for traction. Most chemical outsole makeups are more slippery (salomon) than the industry standard (vibram) - this is a big problem on wet slick rock - and a potential killer in alpine terrain.
>Lug/Stud Length and thread patternMost important in wet conditions, and also on rock and vegetation for not so obvious but practical reasons. Short lugs (like Salomon Quest 4D and most trailrunners) especially if combined with a soft overall sole make a boot slippery in wet earthy/grassy terrain, in steep terrain this can lead to injury or death.
Depending on the terrain one or the other factor is more important for traction. For normal hiking terrain the rubber material and stud length + thread pattern is most important. For off-trail and mountain terrain the stiffness is also important.
