SO many things!
So true.
I have a few but will mention the top 2.
1. When "this generation" was changed in 1995, I had a hard time accepting that "we" were taught for so long that this was pretty much settled sometime shortly after 1914 and was a rock-solid teaching. When I tried to talk to a fellow elder about it, he was older and saw so many things change so he casually said "Things change."
It didn't sit well with me, it didn't fit to just accept that the light gets brighter because the light would have been off with the change of understanding. It was studied at the meeting and someone read the answer to the question about it and then, BAM! All was changed like it was no big deal.
2. I saw so much nepotism, protecting of JW families of elders to the degree that it was a double standard. And then I was taught via elders school and letters that elders could be forgiven for things like viewing pornography without even a judicial hearing or loss of privileges. I started noticing more and more double standards and extra privileges among higher ups.