Do you know anyone who is so uncomfortable saying they don't know the answer to a question that they'll make stuff up? Why do you think they do that?

The question started out “When has a supposed “professional” given you the wrong information?” but morphed into “WHY?”

It’s happened to me a few times. The first two that come to mind was once, in the 90s, right after we moved to this small town from Wichita, I was putting linoleum down on a kitchen floor. I went to the hardware store to get some vinyl wall base. The guy showed me what they had. All of it ran straight down to the floor.
I said, “I need some that has a “lip” on, that curves out a little at the bottom. It’s a lot easier to clean.
He said they didn’t make anything like that.
Well, this wasn’t my first time laying linoleum so I knew he was wrong but I didn’t really have any where else to go within 50 miles so I just went with what they had. (It was a place I was renting anyway.)

Another time Rick and I were looking at some laminate flooring. We had some down in the living room and old Dakota slipped all over the place.
I asked the guy if they made any that was roughly textured, more like real wood.
He said “Nope. They don’t, but that’s a good idea.”
I didn’t know any better at the time so I took him at his word…although having textured laminate seemed like a no brainer to me.
It wasn’t 2 months later, at a different store, lo and behold, there was textured laminate flooring. I asked the clerk how long textured laminate had been around, and he said “Years.”

Why would people make up an answer instead of saying they don’t know?