There were a few missteps in Lu's career. Some he has been very public and candid about, especially during his IG lives and interviews he's conducted. A couple of things:
-Lu's manager being in prison (this effected a lot of negotiations during his career)
-Dissing Obama during his time as president, WHILE TRYING TO PROMOTE A NEW ALBUM
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(Lu himself said this put a stop to a major rollout he was working on and cut most of his media/music connections).
-Signing to Atlantic because he thought Jay was going there. This is one of the biggest miscalculations because it led to a delayed album (Lasers) and him being musically stagnant after releasing the classic known as The Cool. Jay would go on to Def Jam (camel moves).
-Labels actively stopping their artist from collaborating with him (spoke on it during an IG live session). This started happening after speaking on Obama (see earlier reference).
-Kendrick beef? Lu was open at one point about Kendrick taking parts of his persona or creative ideas for himself (Kung Fu Kenny, DAMN being able to be played in reverse a la Tetsuo, Black Panther soundtrack cover, etc). Apologized years later, mentioned that while he still thinks he's the better lyricist, Kendrick makes better music.
-SLR rapping style. Lu is in my top 5 as far as artist are concerned but not everyone wants to play the DaVinci Code to digest music. His music is layered and very complex at times, making it a task for new listeners, since music has been dumbed down for the casual consumer.
Yet, despite all this, he's released some of the best music since being independent. Not a fan at all of these latest singles though.