Be consistent with your inconsistency

Six Sigma is based on consistency - on reducing variation so that processes run smoothly and consistently, to their specification. 

Most processes have some variation - due to  inconsistency of raw materials, variations in machine or equipment performance, human inconsistency and error, variations in  the environment and so on. 

We either have to stop such variations occurring or design the process to be flexible enough to cope with the variation.

If the variations are within acceptable - and planned - limits, the process should be able to  cope.

So, oddly enough, your aim is to control process elements and environmental factors  and train your staff so that you have consistent inconsistencies - within tolerance limits.  If you can get there, give yourself - and your team - a pat on the back.