According to the lecture comparing Lean and Six Sigma, the principles

identify and prioritize customer requirements $(=$ value$)$

identify and optimize value$-$stream $($chain of value$-$adding process$-$steps$)$

implement pull$-$principle and act order$-$related $($JIT$)$

implement continuous$-$improvement$-$process $($CIP$,$ KAIZEN$)$

describe best:

Six Sigma

Lean

Both

Neither