I have. In fact, I just wrote a blog post about it and would be happy to PM you a link (I'm apparently not allowed to in this post).
Most Android phones in existence never or rarely receive updates.
Many of the big, popular brands are getting better at it with their newer phones. Google, BlackBerry, Nokia, Samsung, LG, and Motorola all issue regular security updates on at least some of their phones.
But what about HTC? ZTE? Huawei? Even Motorola and Samsung don't update all their phones.
And I would be surprised if phones older than 2 years, besides the Nexus 5X, Nexus 6P, and BlackBerry Priv, are getting regular monthly security patches.