It means shaky! In this context, rocky is taking its secondary meaning of tending to rock or shake; unsteady instead of its primary meaning of consisting or formed of rock. This is actually an idiomatic expression which means that something was poorly conceived or incorrectly implemented from its start.

It depends upon the context.

If we're talking about a house, rocky would take its primary meaning of consisting or formed of rock, which would tend to imply that it was fairly steady.

If we're speaking metaphorically, however, rocky is likely taking its secondary meaning of tending to rock or shake; unsteady instead. This is actually an idiomatic expression which means that something was poorly conceived or incorrectly implemented from its start.