Here is an example of a broken object from Google that has been gnawing at me for years.
The story occurs every couple of months. I receive an email message from a person I know who has changed email addresses or is writing from a new email address. The person is in my list of contacts. I want to add their new email address to the respective contact item in my list of contacts. This is something that is quite easy with the phone numbers and contacts on a mobile phone. Not in Gmail though.