Short answer: with the massive user-base of this app, they can't replicate in-house every OS/gear/media/plugins/workflow/other-apps-on-machine situation of the user base. What they can't replicate they can't see or fix ... so they need data. Specific and detailed on user troubles.
Please post your troubles on their UserVoice system, including details of your system, gear, media, plugins, and problems. Every post filed there is read by at least one engineer, and all posts are collated and sent up to the upper managers who decide budgets by metrics. This is one of their main ways of getting metrics, so ... it is important for all users with issues to file complaints there.
Long answer ...
Apparently you've not noticed (most people clearly haven't) ... but the last couple "cycles" of Premiere hasn't included any set of massive new toys. Why?
Because working on stability/bugs/performance has been the main goal since Patrick Palmer became the head of all Adobe video apps not yet two years ago. And last year he hired a guy named Ivo Manalov to head rebuilding their entire team to do a better job of 'clean' development catching things early ... and also fixing things what get out into the wild. Even the engineers who's work has changed that I've met at Adobe MAX last, fall love what he's done to and with their internal workflow.
Patrick, Ivo, and a couple engineers were at Adobe's huge MAX conference last fall for anyone to visit with, and they spent some time with the ACPs that specialize in Premiere that were there. And as we're the volunteers on this forum that deal with all the crud that this app can give users, and frequently have some of the same issues ourselves, that means they got some very specific, very pointed questions.
Ivo said the good news was they've worked through a massive list of stability/performance/bug issues that had built up through the years. He was very pleased with that effort. Their figures for number of users that are working without issue is well up from what it was.
The bad news ... this app runs on many thousands of systems a day, across the widest set of machines, devices, media, and plugins of any NLE. They have X number of machines in-house, and of course Y number of machines in beta testers. So ... relative to the user base, the number and variety of machines that it is built and tested on is not ... large.
That presents a massive problem: they simply cannot predict the variety and interactions that users get with the gear, media, OS, and other software across all users. What they can't do in-house, what they can't "see" ... they can neither predict nor fix. So ... they have a relatively small subset of users who are having issues from annoying to getting completely hammered.
But set against the massive number of total users, a "relatively small subset" is still a large chunk of people. Most of whom are having issues the engineers cannot replicate in-house. So ... they need detailed problem/bug reports.
One of the engineers who reads every one of those was there at MAX. His biggest complaint ... not nearly enough detail in most bug/peformance-issue posts for him to get any feel for exactly what is happening on what type systems under what circumstances. "This is broke ... fix it!" Just isn't very helpful. Even just saying "Warp isn't working right fix it stupid!" isn't helpful. Because they need data on your details to be able to do the basic troubleshooting steps required to track things down.
So ... please, for all us users! ... file detailed reports on the UserVoice system for your troubles. Give the engineers enough data to assess why/when/where/how/what is going on for X to happen. And give the upper managers some metrics so they hire more engineers!
Neil