What got me on this topic is recently I've been going back through Korn's discography in chronological order and it's reminded me of how the band did go through a nearly decade long low point. Specifically after their 2002 album "Untouchables" the famous nu-metal act tried to experiment more with their sound, but to mixed results. I do think "Take a Look in the Mirror" from 2003 is mostly good, but their 2005 and 2007 albums, "See You on the Other Side" and the untitled album respectively, don't have a lot of music I find particularly enjoyable outside of a select few songs (like for example I will admit "Twisted Transistor" is a real bop). A band changing their sound for an album or two isn't really a bad thing in of itself, but the overall execution in Korn's case wasn't really the best IMO, and attempts to still showcase the band's signature dark and gritty nature felt flat.
Their 2010 album "Korn III: Remember Who You Are" was a major attempt at recapturing the band's early years, even being branded as a follow-up to both their 1994 self titled debut and 1996's "Life is Peachy," but I gotta admit upon relistening to it I feel the album isn't as strong as it was when it first dropped. I'm not alone in this either, the band members themselves admit the album was weak and was also plagued with production troubles due to producer Ross Robinson trying way too hard to piss off the band members on purpose in hopes it'd reignite the "dark and angsty" nature of Korn's early works. 2011 would see them take their experimentation phase to something of a "major conclusion" by being an album where they would collab with a bunch of dubstep DJs and make a genre hybrid of nu-metal and early 2010s dubstep (often labeled as "brostep"). Now I'll be honest and say for me personally this album is a guilty pleasure, I actually do like stuff by DJs like Skrillex and Noisia, and combining that sound with Jonathan Davis' vocals makes for a nice mix IMO.
What I feel really turned the band around and got them back to being great again was 2013's "The Paradigm Shift," which coincidentally was also when the band's original guitarist, Head, reunited with them (he temporarily left from 2005-2013 in order to get help with his drug and alcohol addictions). Now the album I do feel had a poor choice of lead single as "Never Never" is frankly one of Korn's weakest songs IMO and why it was chosen as the lead single I have no idea, but outside of that one song the album was awesome and felt like a real return to form for Korn, and ever since then I feel Korn's managed to recapture their nu-metal roots in a way much better than their 2010 album.