When you productize, you package your technology into a whole product or service that does a useful job for someone. For example, Amazon productizes its digital content library in form of a Kindle, which the end-user thinks of as “the product”, but which is really just the front-end to a huge back-end service.
When you license, you disclose your raw technology to a vendor in exchange for a fee. That vendor becomes responsible for productizing or relicensing your technology. For example, the Kindle uses an E-Ink screen. But Amazon doesn’t own the E-Ink technology. The E-Ink corporation does. It licenses its display technology to Sony (Reader), to Barnes & Noble (nook), and to Amazon (Kindle).
Licensing is a perfectly honourable way for an inventor to diffuse their innovations. An inventor doesn’t always have to take it all the way through productization and startup. It’s okay to leave commercialization as an exercise for the business pros!