Well if one goes back to 1955 relability was sometimes measured in terms of a few hours of operation(tubes) Now the best systems can get 40,000+ hours under temperature and vibration(Aircraft/Oilfield environment) -- In the 1970's I recall living with the frequent tube replacements on the TV which cost as much as a used car(tubes)
Now for high reliability one faces the challenge of reliability under thermal cycling.
Partly a device issue and partly a packaging issue (newer processes and lower cost devices and packages)
What are the engineering and design challenges in creating successful IoT devices? These devices are usually small, resource-constrained electronics designed to sense, collect, send, and/or interpret data. Some of the devices need to be smart enough to act upon data in real time, 24/7. Specifically the guests will discuss sensors, security, and lessons from IoT deployments.