Originally Posted by puffin
Words are beautiful yet we only use a small proportion of them. I have been criticised for using too many big words and had people complain they can't understand me. Why is this a fault with me rather than the other person?
Many of us have had this experience.
1) Your strength in vocabulary may highlight another's weakness in that area.
2) This is related to another area of strength which many of us may struggle with: Know your audience.
Years of professional experience with individuals having different knowledge bases, including English Language Learners, have gotten some us into a habit of speaking/writing in a thesaurus-like manner... often using two or three different words or phrases in one sentence to define, describe, and communicate the same idea. This casts a wider net for an audience to potentially catch and adopt an idea.

Do any of you play HQ trivia? On weekdays it typically consists of 12 questions. The game show host frequently announces the 11th question as the penultimate question. smile HQ has an audience which enjoys mental stimulation including vocabulary words which may be infrequently used.

ETA: Related post (May 2019)