Lean Six Sigma and Inventory Management

This comes from the fact that whenever an order isobsolete if the product has expired or is not very far
received the goods can be dispatched without delay.off from doing so.
But this often gives rise to a scenario of piling up ofIn such a situation, the customer may reject the
inventory, unless good sales are achieved - or theproduct.
stock becomes outdated.Dealing with Poor Demand, Supply, and Forecasting
There are projects undertaken to improve thisAnother root cause may be due to poor
situation, but often end up giving short-term results.management of the demand and supply process. If
The better solution is implementing Lean tools tothere is poor forecasting, or inaccuracy of data on
reduce excess and obsolete inventory.the demand side and over-projecting sales on the
Lean Six Sigma can be highly effective in bringingpart of the sales team, then inventory levels can be
down huge losses suffered due to excess andoverwhelming.
obsolete inventory.Rework caused due to defects is another major
Analyzing Root Causesfactor that leads to obsolete inventory as well as the
The first step is to undertake the analysis of excessincrease in the lead times. Lean Six Sigma tools can
and obsolete inventory that an organization has. Thebe used very carefully in dealing with this situation.
DMAIC methodology can be very useful in bringingThe phases of DMAIC allow for defining the project
the overall improvement in the inventory scenario.goals, plan the data collection in the measure phase,
Often, the root causes of this results from long leadand carrying out a physical count in the Measure
times, poor forecasting and quality issues. Furtherphase. This helps in understanding the value of the
analysis will show that there are smaller reasonsstock better than the book value. Value stream
linked with each other that lead to the problems.mapping in the Analyze phase helps in understanding
For example, large lead times may be caused due tohow the input variables are affecting the inventory
larger lot sizes. Even if the order cycle time is of 30levels.
days, if the lot size for purchase is 90 days, then thisIt can form the basis for an inventory model. Other
gives rise to a huge amount of inventory. Thoughareas are also identified where the inventory is built
this may not be the only reason, it can be a majorup unnecessarily. Lean tools like 5S can be very
reason along with the cause being one ofuseful in sorting out such a situation. Other
complicated processes.improvement areas are also identified.
There could be other reasons that lead to obsoleteThe Control phase can be an ongoing one, which can
stock. If lead time is great and there happens to beensure sustained improvements.
some rework needed, then the by time the stock isLean can prove to be highly useful in addressing the
ready the utility of the stock may be reduced.issues of excess and obsolete inventory using tools
For example, in a pharmaceutical company, if suchand techniques to identify root causes and designing
large lead times exist, then the stock could beLean solutions to streamline the process.