Delays can be caused by:

Time between steps in a process

Waste and rework

Large batch sizes

All of the above

Lean Six Sigma:

Takes a long time to learn

Has a "long tail" of tools used infrequently

Requires an intricate knowledge of statistics

All of the above

To analyze what customers want use the:

Voice of the business $($VOB$)$

Voice of the customer $($VOC$)$

Voice of the employee $($VOE$)$

Voice of the supplier $($VOS$)$