I know that others find these books just fine. I read two of them, if I remember correctly, and I didn't find them to be up to the standard of Clancy. My brother, who is a bigger Clancy fan than I am, independently came to the same conclusion.
Of course to each their own.
Well, that may depend on what period Clancy you're talking about. I don't find the late era Clancy all that good so it wouldn't be a high bar to clear for the other authors to match that.
My favorite Clancy Books:
1) Hunt for Red October
2) Clear and Present Danger
3) Sum of All Fears
4) Debt of Honor (reading the end of this book after 9/11 hits different)
5) Cardinal of the Kremlin