There’s a myth that you should never price an ebook at $1.99, because it’s the worst price for book sales.
Correlation is not causation.
1. Most e-books at $1.99 will be short stories, since pricing a novel there is pointless.
2. Novels generally sell better than short stories.
3. There are a lot of novels at $0.99.
Therefore, as a group, books at $0.99 will sell better than books at $1.99.