I'll have to go digging, as many of those failures were from the 2014-2015 time period. Most were HTU21D's with a few from the SHT series (some of those SHT's had sintered shrouds -supposedly for burial).
I've a few BME280's out now and some have already begun exhibiting the same basic problem: normal operation up till about 95% RH, then a rise to 100% and staying there.
Because they reset to apparently normal operation after being dried out. I'm not even sure this can be called a "failure" exactly. It should probably be described as using those sensors outside the environment they were designed for (ie 90-100% humidity for extended periods of time)