Damage increases.I'm fine with not providing ability-score boosts at certain levels, or magic items that do the same. But ability-score caps are just the lazy-mans solution to the problem.
There does however have to be progression in some form. Attacks get more accurate, more powerful, something. Gaining new "options" is neat, but ultimately pointless if none of the options are explicitly better than the others.
That aside, no growth in abilities directly punishes the non-Vancian. A Wizard doesn't ever need more than an 18 Int, but they keep gaining more spells of increasing power. A fighter who gets no stronger, hits no harder, or more accurately is just a pile of HP, he gets nothing.
Given the abstraction of HP and hitting with tracks in the first place, doing more damage can be directly analogous to better aim and more force/skill with an attack.