This is lean

Question 1

What are the 2 types of efficiency?

Answer 1

1) resource efficiency
- focus: resources
- utilize resources and maximize capacity utilization (value adding time/available capacity)
2) flow efficiency
- focus: flow units
- fulfill needs (value adding time/ throughput time)

Question 2

What is a process?

Answer 2

Sequence of activities designed to fulfill needs

Question 3

What are examples of flow units?

Answer 3

information, material, people

Question 4

What is the difference between value-adding time and non-value adding time?

Answer 4

when is value created for the customer?
looking at non-value adding time is primary way of increasing flow efficiency
Faster is not always better!!

Question 5

What are direct vs indirect needs?

Answer 5

• direct - outcome
• indirect - experience

Question 6

What determines the share of direct and indirect needs?

Answer 6

nature of service, occasions, people

Question 7

What is little’s law?

Answer 7

Throughput time = flow units in process*cycle time
–> consider people in queue and speed of how the queue is moving

Question 8

What is the law of bottlenecks?

Answer 8

before bottleneck - pile up
after bottleneck - waiting time
bottleneck determines speed

Question 9

What are the conditions of bottlenecks?

Answer 9

1) serial dependence
2) variation

Question 10

What is the VUT relationship?

Answer 10

Variation, utilization & throughput- time
The more variation the longer your throughput time will be at a given utilization

Question 11

What are the 4 dimensions of the efficiency matrix?

Answer 11

(horizontal - flow efficiency; vertical - resource efficiency)
Wasteland, Efficient island, The perfect state, Efficient ocean

Question 12

What is the efficiency frontier?

Answer 12

In the efficiency matrix - variation decreases the possibility to reach perfect state (star)

Question 13

What is the efficiency paradox?

Answer 13

Which form of efficiency should we prioritize?

Question 14

What are the effects of resource efficiency?

Answer 14

• throughput time - long
• number of units - many
• restarts - many

Question 15

What are the effects of flow efficiency?

Answer 15

• throughput time - short
• number of units - few
• restarts - few

Question 16

What are consequent effects when focusing on resource efficiency?

Answer 16

• long throughput time –> trigger other effects
• more flow units –> notion of inventory
• more restarts –> call center

Question 17

When focusing on resource efficiency, what can happen?

Answer 17

Secondary needs - needs that customer has and you want to fulfill them but you engage in superfulous work

Question 18

What is superfulous work?

Answer 18

• wasteful and not wasteful at the same time
• we create problems ourselves we need to fix

Question 19

What is the efficiency paradox?

Answer 19

by not focusing on utilizing capacity, we free up capacity (just because you are busy, doesn’t mean you are adding value)

Question 20

What is lean operations strategy?

Answer 20

move right and up (first focus on flow efficiency, then on resource efficiency)
you notice different problems in process –> address problems –> remove superfulous work –> increase resource efficiency

Question 21

Why is continuous improvement important?

Answer 21

static goal - once you reach the goal, you’re done
dynamic goal - constant improvement (i.e. Toyota)