Why was Lucius Fox fired?

Question

In Batman Begins there is a scene where William Earle fires Lucius Fox. I just watched the movie for the first time so I may have missed something, but it seemed out of place.

At the time he is fired there is no reason provided, but there is a quote later when Lucius is speaking with Bruce which states the apparent reason:

Lucius Fox: [about the microwave emitter] Earle just fired me for asking too many questions about it.

It appears we have a cannon answer, but it doesn't seem like a very good one. So, are we given any more clues as to why he was fired or is there anything to support that he was fired for asking too many questions about the emitter?

It seems odd that Earle went to Lucius to tell him about the emitter and ask him for information and then to fire him for asking too much about it. Fox was already banished, if there was another reason I assume he could have just been fired earlier.

Answer 1

It's also because the board wants Wayne Enterprises to go public, and Fox doesn't believe in breaking up Thomas Wayne's legacy. They successfully do this, but then, Fox is heavily involved in keeping Bruce in the loop, keeping him well informed and well guarded. This is bad news for the board having control of the majority shares. Fox rattles cages and it is messing up their plans.

Answer 2

To be honest, that was something which also bothered me when watching it the first times. Why fire him just for asking this single question? But it certainly makes sense, even if probably not written that well:

Fox has always been a thorn in the eye of Earle, who banished him into the dead end the R&D department is (or was). So when going to him he just needs some information about this emitter. But Lucious asking this slightly curious question ("you don't miss one, do you?" or something similar) was probably a bit too much for Earle's nerves at this point and he probably also intepreted a bit of a spitefulness into this question (which might even have been intended by Fox). So at this point Earle was just too fed up with Fox and did what he was going to do sooner or later anyway.

EDIT: And as Morpheus adds in his comment, Fox also makes a good scapegoat to blame for the loss of such a valuable R&D item.