Well, I don't know enough about that period to be able to give you a reliable answer, but this is the sort of thing that Reformation scholars spend much time debating. One important thing to bear in mind here is that at that time - and indeed at most periods before now, possibly including now - you couldn't really distinguish between theological factors and other factors. Everything was so closely bound up together. I mean, you can't distinguish between "inside the church" and "the surroundings"; the church was everything and everything was the church. This is why popular presentations of, say, the Galileo affair are misleading; it wasn't Galileo versus the church, because Galileo was part of the church. It was some elements of the church versus other elements of the church. The same is true of the Reformation. That said, I think that in many ways the church was in a pretty bad state by the time of the Reformation; it's hardly surprising that something major happened. But then, was it in a worse state than (say) the mid-fourteenth century? Hard to see how it was. So why did Luther have such a different career from Wycliffe? You can certainly point to (partly) non-theological factors, such as the fact that Luther was protected by local rulers. And other German princes endorsed his movement enthusiastically, simply because it was a means of asserting their own authority, not because they particularly agreed with or even understood his ideas. Plus I'd say that Luther was simply a more able thinker than Wycliffe (whose book on universals is one of the weirdest pieces of philosophy I have ever read). But all of this is true of any large and complex historical phenomenon, religious or otherwise. You can't usually isolate particular events and say these were the ones that caused it; it was caused by all of them.