They ignore you, don't listen to you, make you repeat yourself 100 times, pass you onto other people, and never get anything done for the most simple of questions. Why is it so terrible even for someone who has been a customer for many years?
Adobe is no worse than chatting to Amazon support, but yes, at the end of the day it's bad. 😉 That said I'm with @pixxxelschubser: It would be more useful to explain what you are having issues with so we can point you to the proper resources and offer assistance.
Sorry to hear about this experience. Would you mind sharing a few details, like the exact version of the OS and Illustrator installed on your computer, system configuration (CPU/GPU/Memory/Display), and a screen recording of the problem so that we can investigate this further?