The Auto-advance feature automatically shows the next conversation instead of your inbox after you delete, archive, or mute a conversation. You can select whether to advance to the next or previous conversation in the "General" Settings page.
These days, many startups are being created to help you reach inbox zero and stay there. So it was expected that Google wasn’t going to stay behind in the race. I recently came across a Gmail Labs’ Auto-advance feature (an experimental feature basically) that forces you in reaching zero unread emails in your inbox. The new feature called “Auto-advance” is simple and easy to use.
The lab shows you the next email in your inbox as soon as you delete or archive any mail. That is, instead of going to the inbox view, you are presented with another unread mail. This has its own pros and cons though.
One of the pros is that you can make your make your inbox clutter-free in a single session and maintain your unread emails in the inbox to zero. Instead of going back and clicking every individual mail and then archiving it, you are presented with them one after the another.
The con being that it can be awfully painful at times. In-fact, it is a pain to sit for the first time to go through each unread email. And if you receive loads of emails every day, it might be difficult to go through all of them one after the other. Actually, all you wanted to do was reply to that one important mail but now you are stuck reading many of them since as soon as you are done responding to one, another one pops up asking for your attention.
So overall, the usefulness of this Gmail labs feature is dependent on you, your email usage and preferences. If you are someone who deals with all emails in batches and can’t resist unread mails, go ahead and turn on auto-advance in your Gmail labs. But if you are a person who practices procrastination, this isn’t the right option to use. It might be a pain for you instead. Your will-power might be worn down by it, so you are better off without it.
So to conclude, people who wish to reach inbox zero, auto-advance does have its uses for you, and for the rest of you, inbox zen is probably better than turning on this feature.