A lot of people ask us if or why don't we support device "X" with TWRP. The cold hard truth is that TWRP is a free and open source project. Pretty much all of our revenue comes from ads and donations and those revenue streams don't amount to a whole lot of money. This means that we don't have a lot of extra revenue to buy devices for porting TWRP. The vast majority of devices that we do own are bought with our own money and not with "TWRP money."
Since TWRP is open source, rather than depending on the community to buy or pay for devices, we're depending on the community to port TWRP to their devices and help provide technical support for those devices. We spend a fair amount of time maintaining our guide for "How to compile TWRP from source" so that others can get involved. We've set up a gerrit instance so that people outside of team win can easily contribute code to TWRP. We've made significant improvements to the TWRP code base so that it is easier than ever to get started compiling TWRP for your device.
So, if your device isn't currently supported by TWRP, feel free to step up and follow the guide and try to get TWRP working on your device yourself. If you run into trouble, join our IRC channel (#twrp on Freenode) and ask a question. Just remember that we have lives outside of TWRP too so you may not get an immediate answer in IRC. You can also ask questions via Contact Us on our website. We'll do our best to help you help us. If you can't do it yourself, ask a developer for your device to see if they might be interested in doing a port. And of course, you're always welcome to loan or buy us your device if you're so inclined.
For the most part, we're going to get out of the process of attempting to port TWRP ourselves to other devices that we don't have in our hands. We may still attempt to port a few devices, depending on demand and difficulty. However, it is much more time consuming to port TWRP while relying on external testers. We'd rather spend that time adding new and exciting features to TWRP. Hopefully you will agree.