I'm not sure what you mean. They used daily weather reports to decrypt the enigma for that day, so I'm not sure how that is an operational failure. If you know part of the cleartext, it's possible to brute-force any encryption given enough time.
Sure, but those known text attacks were made significantly easier by German operators using (and reusing) non-random and easily guessable encryption parameters. Once the keyspace became small enough to search, they were able to brute force the encryption.
You're mentioning one technique as if it was the comprehensive method of compromising the Enigma. It was not. The example you give would only work for the Kriegsmarine transmissions for example. The Luftwaffe had its own system with its own operational failings.