Both hydrarch and xerarch successions lead to

The succession of plants is named hydrarch or xerarch depending on the nature of the habitat, whether it is in water (or very wet places) or in very dry areas. 

In moist locations, hydrarch succession occurs, with the successional series progressing from hydric to mesic conditions. Xerarch succession, on the other hand, occurs in arid places, and progresses from xeric to mesic circumstances.

As a result, both hydrarch and xerarch successions result in medium water conditions — neither too dry (xeric) nor too wet (hydric).