The Hamlet Project

This sense of flaw seems like one that Shakespeare could have made up. The word feels like a combination of flood, froze and thaw. Like it’s a word that should exist instead of one that did. But it would appear that flaw once meant flake, as in snowflake. So when snow fell in the 13th century, folks might say “Look at all those flaws!”
“I caught a flaw on my tongue!”
Or when it’s a clear day and suddenly a snowflake seems to appear – “Was that a flaw?”
How did this word shift meaning so dramatically?
I know its sense of flake expanded outside of snow – that you could have a flaw of fire or flint at a certain point …but then from there – how did we get to a sense of blemish or mistake?