Lean & Flow

Value Stream Mapping is primarily used in DevOps to achieve what?

• A To design the user interface of an application
• B To replace all automated testing
• C To assign salaries to team members
• D To visualise the steps, delays, and handoffs in a process and identify where value is added or lost ✓

Answer: Value Stream Mapping visualises the end-to-end flow of work, exposing delays, handoffs, and waste so teams can target the biggest opportunities to improve flow and reduce lead time.

In Lean thinking applied to DevOps, what does the term 'waste' (muda) refer to?

• A Any activity that consumes resources but does not add value for the customer ✓
• B Only the physical materials thrown away by a factory
• C The time spent on customer feedback
• D The cost of purchasing automation tools

Answer: In Lean, waste (muda) is any activity that consumes time or resources without adding value to the customer, such as queuing, rework, handoffs, and partially done work.

What is the purpose of a Work-In-Progress (WIP) limit on a Kanban board?

• A To increase the amount of work started simultaneously
• B To remove the need for prioritisation
• C To cap the number of items in progress so flow improves and bottlenecks become visible ✓
• D To guarantee that every task is completed on the same day

Answer: A WIP limit restricts how many items can be in progress at once, reducing multitasking and context switching, exposing bottlenecks, and improving the overall flow of work.

According to the Theory of Constraints, how should an organisation improve the throughput of a system?

• A By identifying and improving the single biggest bottleneck (constraint) first ✓
• B By adding as much work-in-progress as possible
• C By ignoring constraints and focusing on local efficiencies
• D By optimising every step equally and simultaneously

Answer: The Theory of Constraints holds that a system's throughput is limited by its biggest bottleneck, so improvement efforts should focus on that constraint before optimising anything else.

What does 'lead time' measure in a software value stream?

• A The time a developer spends in meetings each week
• B The number of servers in production
• C The elapsed time from a work request being made to it being delivered to the customer ✓
• D The total cost of the development tools

Answer: Lead time is the elapsed time from when a request or piece of work is made until it is delivered to the customer, and reducing it is a central goal of improving flow.

Why does reducing batch size generally improve flow in a DevOps value stream?

• A It speeds up feedback, lowers risk per change, and makes problems easier to isolate ✓
• B It removes the need for automated deployment
• C It forces all work to be done in a single large release
• D It increases the risk and complexity of each release

Answer: Smaller batch sizes accelerate feedback, reduce the risk and impact of each change, and make it easier to locate the cause of any problem, which improves overall flow.