I thought it might be beneficial to hear other people's (including Esri's) thoughts on the quality and stability of the code powering ArcGIS Enterprise. There are two main reasons I bring this up. One is my organization is still trying to recover the full functionality of our ArcGIS Enterprise site after upgrading from 10.6 to 10.6.1 about a month ago. This will be the third time we have upgraded Portal for ArcGIS, ArcGIS Server, and ArcGIS Data Store. Each upgrade has had issues (mostly with ArcGIS Server). Fortunately up until now, we have been able to fix whatever was broken during the upgrade.
The second reason is how the new versions of Insights for ArcGIS and ArcGIS Enterprise 10.6.1 have been released. ArcGIS Enterprise 10.6.1 was released in July, but a compatible version of Insights for ArcGIS was not release until this week. The only warning not to upgrade was a generic note in the ArcGIS Enterprise 10.6.1 help documentation to make sure you have compatible versions of Workforce and Insights before upgrading. While Workforce help documentation told which versions of Workforce were compatible with which versions of ArcGIS Enterprise up to 10.6.1, the Insights help documentation was not updated for 10.6.1. You had to find a post here on GeoNet to know for sure that Insights 2.3 was incompatible with Enterprise 10.6.1. Move on to the release of Insights 3.0 and now Esri has a warning on the download page to still hold off on upgrading because now ArcGIS Enterprise 10.6.1 will need to be patched for Insights 3.0 to work correctly. Unfortunately, the needed patch is not available yet. My problem with this whole scenario is not that the initial releases of ArcGIS Enterprise 10.6.1 and Insights 3.0 were not in sync, my problem is how poorly the situation was communicated to customers. An email, a blog post, or at least a tweet to let customers know that if you are using those products that you need to wait to upgrade would have been great.
Personally I would like to see a quality improvement release over a new features and functionality release, and an emphasis on ArcGIS Enterprise components being compatible with the current release of ArcGIS Enterprise. We have been using what is now called ArcGIS Enterprise for two years and are getting closer to moving most of our users off of ArcMap. So we now have lots of content and users on ArcGIS Enterprise, but now every upgrade makes me worry that it will cause us to have to rebuild from the ground up (well from backup at least).