Your connection is not private

Attackers might be trying to steal your information from {website url}(for example, passwords, messages, or credit cards). Learn more
NET::ERRCERTAUTHORITY_INVALID

What's Wrong?
Google thinks all websites should be secure so they are starting to forcefully "nudge" people in that direction.
Google announced in late 2016 that they would start showing a warning in the address bar if a page that asks for credit card information or a password is not served over https.

In January of 2017 Google announced that the warnings would become more prevalent, showing up below the form itself in the Chrome 57 browser which was scheduled for release in mid-March 2017.

Why should you as a small business care about this? Google wants all web traffic to be secure eventually. Security is one of Google's top priorities and as you may know when it comes to the web Google usually gets what Google wants, one way or another.

How can Google force this on you? Easy, they make it part of the algorithm they use to determine what results show in search and how they are ranked. Secure pages, even those without a credit card or password field will be weighted higher is search. If you want to show up, serve pages over https, that's the bottom line.

No one outside of Google knows for sure when this will happen, but it may be starting to happen now.  Users already see "Non-Secure" warnings, and they are more verbose than before.

Do you want a visitor seeing a message like "Warning Your connection is not private" when they visit your site? What will that do to your page views? What will it do to your lead capture or sales?

For more information and what you can do about it please read HTTP -vs- HTTPS, Why You Should Care.