Why do strong acids dissociate (almost) fully on a molecular level? In the Brønsted-Lowry theory, strong acids $\ce{HA}$ dissociate using water and react into hydronium ions and the conjugate bases $\ce{A-}$. However I never understood in the strong acids case what stops the products of the reaction(ions) into reforming chemical bonds (why the reaction is one-way) and what enables them when the reagents aren't strong acids. How is this explained macrocosmically and microscopically?
Deprotonation is always a reversible reaction. Hence why, even strong acids, have $\mathrm{p}K_\mathrm{a}$ values (which rely on the presence of equilibria).