To the extent we allow ourselves to doubt, we open the opportunity for growth in understanding and progress. In other words, the road to improvement and transformation necessitates a letting go of the idea that we already know and therefore don't need to question and continuously re-evaluate. Anyone who is absolutely certain of their current correctness on any subject is blind to the possibility of error, no matter the evidence. Somehow doubt must penetrate our mind before a more correct comprehension can be achieved.
The above observation applies to our religion as much as anywhere else. Many are blinded by the assurance that past generations firmly established the correct theology; and, therefore, theological change could only be a move away from the truth. The pursuit of understanding is never far removed from the act of questioning. When questions cease, learning stops. One can mechanically regurgitate what has been said in the past and call that learning; but, in fact, such represents no more than the educational achievement of an electronic recording device.