disincentives — Most devs would need to pay out of pocket to host Alexa apps after June. Enlarge / The 4th-gen Amazon Echo Dot smart speaker.Amazon Alexa hasn't worked out the way Amazon originally planned. There was a time when it thought that Alexa would yield a robust ecosystem of apps, or Alexa Skills, that would make the voice assistant an integral part of users' lives. Amazon envisioned tens of thousands of software developers building valued abilities for Alexa that would grow the voic...