One of the biggest challenges in the practice of continuous improvement lies in answering questions like 'What do we do next?' or even 'Where do we start?'. Rooted at the tangible intersection between physics and manufacturing, the Theory of Constraints offers a practical approach to streamlining your process and maximizing your ability to deliver. It provides concepts and tools to identify likely 'tipping points' where applying a small amount of effort might yield large results. Join us for an overview of the Theory of Constraints and an exploration of how this all applies to the business of delivering value in an Agile (or not so Agile) environment.
The Theory of Constraints (TOC) is an idea created by Eliyahu M. Goldratt and popularized through his book The Goal.
15. In Closing
1. A balanced system… isn’t.
2. Every system has a constraint.
• Find it, exploit it, subordinate
to it, elevate it, repeat.
3. What is the goal?
4. Shift from Individual to
Team measurements.
5. And once again…
Limit WIP, Limit Inventory
DAVIDhttp://www.crowtege.com/2012/01/30/nature-deficit-disorder/- - Round 1 was a balanced system (next slide)
DAVIDA common goal is to balance your system:- “A balanced [system]is where the capacity of every resource is balanced exactly with demand from the market.”Assumptions: Keep everyone is busy working all the time; Idle time is “waste”; If we aren’t moving fast enough, we add more people;Misc: Gantt charts encourage planning far into the future based on “balancing” work evenly across individuals and trying to keep everyone busy all the time.http://www.nimblefitness.com/wp-content/uploads/2010/09/Healthy-Balance-1024x681.jpg
DAVIDYour speed depends on the person in front of you. The ability to go faster than average is restricted. There are limits to your speed, but there is no limit on your ability to slow down or stop. Dependency limits the opportunity for higher fluctuations. The gaps increase farther down the line because they have to make up for all fluctuations in the line in front of them. The person at the back has to make up for all the slowness in front of them.Reality: Fluctuations don’t even out; People at the end constantly trying to catch up but can’t;Statistical Fluctuations & Dependent EventsYour speed depends on the person in front of you. The ability to go faster than average is restricted. There are limits to your speed, but there is no limit on your ability to slow down or stop;Dependency limits the opportunity for higher fluctuations. The gaps increase farther down the line because they have to make up for all fluctuations in the line in
DAVIDConstraint @ the backNo idle time!But, gaps are widening as they move forward. (more inventory)Throughput is still… terrible. The last person is determining the throughput. (high cycle time)It doesn't matter how fast any of us can go - it only matters how fast the slowest can go. The slowest person governs throughput“PM is walking by, I’d better look busy”Cost of change is higher in a long line vs. the short line.
DAVIDRound 4a – Constraint at the frontGaps briefly form and then are reduce;Faster people behind slower people can use excess capacity to “catch up”;Inventory is minimal. But.. fast people start grumbling; Fast people still have capacity left over (can’t pass the person in front of you!)The idea isn't to get there the fastest individually, but as a group!It doesn’t matter how fast you go at the front, you’re not “done” until the last person arrives.To go faster (as a group) you have to figure out how to get the slowest to go faster. Round 4b – Can share excess with other peopleUses the resources you already havehttp://thecityfix.com/blog/thecityfix-picks-december-10-dubais-transit-hopes-wasted-parking-in-america-u-k-emission-cuts/
STEVE“To make money”Outcomes!Change the world!Sad faces to happy faces!"the goal is not to keep people busy; the goal is to generate useful output"
DAVIDCost AccountingFocus is on the individual - Keep individuals busy @ 100% each No down time, no slack time for improvementsThroughput AccountingFocus is on delivering value (as a team) [Throughput] Salaries are seen as buying time from employees [Operating Expense] Knowledge/training is an investment [sunk Operating Expense, available Inventory]
BOTH
STEVEFind the constraintInventory, work piling up, downstream resources are idleExploit the constraint –“You can increase the capacity of the whole team by increasing the speed of the bottleneck”“If you lose any time at the bottleneck, it is gone forever, you can’t make it up!”Remove non productive work. Keep this constraint working at all times.Avoid distractionsRemove multitasking & task switchingEnsure that they always have something to work on (create a small buffer in front of them)Let the constraint pull – don’t pushCarefully prioritize their workSubordinate everything to the constraintHave a quality check before the constraint (test first!)Have everyone else work at their rhythmFeed them ‘work’ or ‘material’ in the way that best suits themElevate the constraint.TrainingCoachingBetter ToolsFastest, better computerMore peopleThis one requires the most investment, so do it last.Again.The constraint moves.
SteveConstraint = small diceExploit = Move it to the front of the lineSubordinate = Everyone move no faster than the constraint.Elevate = Share extra rolls to allow the small dice to go faster.
SteveBall Point Game as a class of problemsConstraint = Hand-offs between peopleExploit = Remove non productive work by shrinking the size of your circleSubordinate = Increase quality by dropping vs. throwing. Move your arms more vs. throwing.Elevate = Pass 3 balls vs. 1 ballAgain = repeat!Waterfall as a class of problemsConstraint = hand-offs between people (look for the inventory)Exploit/Subordinate/Elevate = Move communication to the ‘front’ by co-locating, reducing documentation, stand-upsvisual boards
DAVIDA system based on TOC is more predictable than a balanced (or unbalanced) system.Physics proves the benefits of agile/kanban
DAVIDUsing slack time “for free” to improve qualityGet “extra” capacity for free without adding peopleSlack time/sharing/exploiting and their relation to cross functional teamsTDD & TOC