Even though Gmail features one of the best spam prevention, detection and anti-spam technology, it still sometimes fails to differentiate between the good, the bad and the ugly.
Realizing the fact that no technology is 100% accurate or fool-proof, the Gmail team has introduced a new filter called 'Never send it to Spam' which can be used to prevent mails from being auto-marked as Spam in Gmail.
Filters in Gmail are very useful to perform actions on the Incoming email messages passively.
The new 'Never send it to Spam' filter can be used to catch important emails which otherwise may get caught as Spam by Gmail.