What I've heard:
The most expensive watch is not the most accurate or reliable.
The most accurate and reliable watches have the longest wait times to order new, though.
Discussion
What makes a watches more reliable than an other? 🤔
Basically never breaking unexpectedly, and keeping time really well.
I say "really well" as in like, slow enough drift that a person can stay within a few seconds of exact time by adjusting every few weeks or months or years.
Some watchmakers are obsessed with perfect accuracy and go beyond "really well" but durability kinda conflicts with accuracy so their watches end up less reliable