If the password cannot be found after these three options, it is considered too strong to crack and is skipped. This question has been debated since passwords where first implemented. Avoid using passwords that you need to write down to remember. A good password should be at least 8 characters in length. Use words that cannot be found in a dictionary to improve your password's strength and to make it more immune to brute force attacks.
Misspelled words are also good.
Adding special characters such as commas, periods or semicolons improves it to where it will probably not be cracked by brute force. Dictionary words with a special character inserted in the middle so that it cannot be cracked by a dictionary lookup are easy to remember. Finally, if the operating system allows, add special 8 bit characters, such as Kanji or accented characters, will make the password virtually uncrackable. Another trick to finding a password that is easy to remember is using a common phrase, where you take the first character of each word and combine them. Add additional special characters and you have a strong password.