There is actually a term for this. It's called "entrenchment".
People make decisions based on a perceived cost/benefit analysis. There is no actual analysis done in the methodical sense of the word, but merely on an intuitive basis. Someone perceives an idea and a lightning calculation is done that instantly tells them (rightly or wrongly) that the cost of accepting such an idea is far too high. The more time, energy, money and effort has been invested into their current paradigm the harder it is to ever break them out of it. It simply costs too much. Imagine a pastor of a church, or anyone with a long standing ministry having to alter large swaths of the doctrine that they not only have spent years learning and teaching to others but that they also make their living from. Every friend they have probably exists within the orbit of that ministry. You couldn't hardly find anyone more deeply entrenched than that.
For this reason, paradigm shifts must be approached slowly, methodically and with extreme care. Each step that is taken on the path leading to the new paradigm has to be accepted fully all along the way and when the destination is arrived at, the whole path taken to get there has to be visible in the mind's eye such that it seems that no other path could have been taken. They have to feel like they arrived there under their own power and when the light bulb moment happens, they have to feel like they would have flipped the switch themselves had they known the switch existed. Otherwise, the new paradigm will definitely be rejected. It may be rejected anyway, but if there are plausible excuses to do so, the likelihood of the rejection is increased exponentially, especially for those who are deeply invested into that which they have to walk away from.
