We see the confusion, from time to time.
I have to reset my password, each time I login to Blogger!This blog owner may not completely understand the relationship of his (non Google) email account to his Blogger account - and the difference between that account, and a Blogger / GMail / Google account.
If you setup a Blogger account that's based upon a GMail email address, you have to prove ownership of the GMail address. The GMail address is also a Google account - and you prove ownership of a Blogger / GMail / Google account, by providing the correct password for the account.
A Blogger / Google account, that's based on a non GMail email address, is different from a Blogger / GMail / Google account - when the account is not based on a Google Apps provided email domain.
The differences between a Blogger / GMail / Google account, and a Blogger / Google / non GMail account, start with the setup process. The differences are subtle - but not trivial.
If you setup a Blogger account that's based upon a non GMail email address, Google should send a notice to the non GMail email address, requesting ownership confirmation.
Many web services verify email addresses, when used to register their services. If Blogger were to do this, it would provide account verification, similar to verification provided when setting up a Blogger / GMail / Google account.
Google, however, makes it easy to use a non Google email address, when setting up a Blogger / Google account. Just enter the non GMail email address, and you're done.
If you entered the address of a non GMail email account that you do not own - or that does not exist, this is not a problem, during the Blogger account setup process. Maybe later, this will be a problem, for you - or for somebody else. But it's not a problem, right now.
Now, you have a new Blogger account, and you can accept membership in someone else's blog, create your own blog, and / or Follow the blog(s) that interest you.
When you change the password of a GMail based Google account, the password for the Blogger account also changes - since this is really one account. If you delete the GMail or the Google account, you'll have a problem - since this is really one account.
If you want to change the name of a Blogger / GMail / Google account, you will have to create a new Blogger / Google account, and transfer control of assets (such as Blogger blogs) to the new account. This is inconvenient - but it forces you to acknowledge that you are creating a new account.
What if you rename a non GMail email account that you own, or change the password for that account? Any changes you may make to any non GMail email account will not be mirrored in the corresponding Blogger / Google account - since these are two separate accounts.
If the non GMail email account is deleted, for any reason, you can survive, since these are two separate accounts.
- You delete the account, intentionally.
- You change ISPs, and lose the old email account.
- You graduate, or leave the job, where the email account is based.
When you try to sign in to Blogger, using an account that cannot administer a specific Blogger blog, you'll have more challenges. With Blogger never telling you what account you should be signing in, you'll never know why you cannot administer your blog. If you try to recover ownership of your blog, using an account that you do not own, you'll get nowhere.
There are various obscure problems involved, when using Blogger accounts based on non GMail email addresses. A Blogger account that's based on a non GMail email account that's provided by your employer, ISP, or school may be migrated to Google Apps hosted email - and you may lose Blogger access when that happens. Also, email from Blogger, for comment moderation / notification, or for private / team blog membership invitations, may present a challenge.
What you will have to do is understand the issues, such as outlined here. If you don't understand these issues, you'll have problems that Blogger can't help you with, and that you can't solve.