I believe Garmin Express now schedules a daily task in the Windows OS task schedule to run ExpressSelfUpdater.exe every day with highest privilege. As far as I know, this is done without user consent or notification. I trust Garmin and doubt the program does anything nefarious. But I object to the hidden intrusion anyway.
The insertion contributes to task clutter making it harder to spot other possible threats. Also, I prefer to know if software I install has the ability to execute itself without my knowledge, even when it's from reputable companies. Now, if I want to keep my task schedule minimized for simplicity and security, I must go into Task Scheduler after each Garmin Express update to remove the unwanted task. While I trust Garmin's integrity, I have less faith in its code-writing. Garmin Express is a terrible storage hog, considering the simple tasks it performs.
I also think it's slightly deceptive of Garmin. For years, Garmin Express reset an option to start at OS startup each time Garmin Express updated. Garmin dropped that intrusive policy, possibly as a result of customer complaints. Now, it's doing something similar more covertly. And I don't see a legitimate purpose since Garmin Express still checks for updates when the user opens it.
I expect Garmin dismisses objections this because many other companies do the same thing and because what I'm calling an intrusion is convenient for many customers who want the Garmin software to run automatically in background and that notifying them would be an unnecessary burden. That's probably true. I am just not one of those customers.