Hmmm, good question...
IMHO...
AVR reliability is a crucial issue, starts with:
- Stable hardware design
- Debugged/validated firmware
- Utilizes quality internal components
- Comprehensive, HDMI/HDCP certification
- Quality oriented staff/team & assembly location
The challenge today is that the majority of home theater CE products are assembled by subcontractors, not in factories owned by the primary brand. For example, Inkel (Sherwood) factory in Vietnam assembles AVRs for Denon, Marantz and others @ 1 time they were building 75% of all brand Dolby surround AVRs. NAD, Anthem AVRs are assembled by Anam in Vietnam who used to build the Marantz, Harman/Kardon but now concentrates more on price-point low/mid-range integrated amplifiers for NAD, Onkyo, Pioneer, Denon, Marantz selling largely to Europe, Asia and Oceania destinations. Also note that Anam also just opened a 2nd factory in Vietnam mainly building BT loudspeakers and sound bars. As I have posted multiple times, in my opinion supported by real-world statistics, Yamaha AVRs are the most reliable AVRs. They own/control the entire development, parts procurement, certification, mass-production, quality-control processes for their branded AVRs built in their own Yamaha owned factories in Malaysia. However do note that the entry-level, Yamaha branded integrated amplifiers are built by Anam in Vietnam.
1 other point a key reason, Vietnam is a popular location for a CE factory besides slower labor costs is due to certain global trade agreements that allows exports to be tariff-free. This exists today for Europe, but unfortunately this was nixed as the TPP agreement for North America was vetoed by Trump.
Just my $0.02...