We always encourage you to use strong passwords for any account, but because your G account is linked to many other services that you use also, including Gmail, it’s particularly wise to use a smart password for your main Google account.
If you currently have any dictionary words, meaning any word that is grammatically correct, in your Google password, you may want to consider changing it for better security against dictionary attacks and brute forcers.
A strong password will not make any sense, and involve uppercase and lowercase characters along with numerical characters and other symbols.
For example: OtT2359%$8*#^:)
Strong passwords like these are more difficult to remember, but they are important to strong account security.
"Way 4. Use Strong Passwords --Secure your Google Account"
Reference : online-tech-tips.com