Very much associated with inability to hear vast majority of components one may be contemplating purchasing. And then, even if you can, really need an audition to hear in your system, and then that audition may need to be longer term to fully discern sound qualities.
Add to that so many choices today.
And then, as our systems evolve and become more transparent, resolving we can hear minutiae formerly unheard, makes for more exacting process to choose the component that has perfect synergy with rest of system.
Along with above evolution comes evolving cost factors, price to play continues to rise, more money on table may create more anxiety.
No doubt competitiveness comes into play for some, in order to be considered expert one has to have best. Humans do love their hierarchies, and most like to be at top.
I'm sure others will have much to say on the whole subject of insecurities in this so called hobby.