This article is from the Progressive Music FAQ, by Phil Kime(Philip@kime.org.uk) with numerous contributions by others.
No. This is a common misconception. Though we call them "progressive
music artists", the artists themselves are not progressive - the
music is. Once progressive does not means always progressive. There
are many examples of bands that once made great progressive music,
but have turned to churning out worthless pop music. There seems
to be a trend from progressive music to a more accessible form
of music in many bands' histories, and unfortunately, they rarely
return to what many perceive to be their best work.
 
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