79. Project Management Triangle aka The Iron Triangle + FREE CHEAT SHEET // Grab your FREE Cheat Sheet: http://bit.ly/waterfall-vs-agile
Today's episode goes right back to one of the fundamentals of old skool project management:
The legendary "Iron Triangle".
There's a good chance you've never heard of the Iron Triangle: I've rarely heard it mentioned in the context of Agile.
Does it even apply to Agile? I'd love to know your thoughts.
Oh, and be sure to watch to the end for news of the newly-updated "Waterfall vs. Agile Cheat Sheet".
Music: 260809 Funky Nurykabe: ccmixter.org/files/jlbrock44/29186
Today we'll look at a stalwart of old school project management - the Iron Triangle. And I have a new version of the Waterfall vs Agile Cheat Sheet for you. Welcome to Development that pays Cutting-edge strategies for profitable Software Development My name is Gary Straughan. The Iron Triangle. Forged in the fires of Mount Doom What's that We couldn't get the graphic What did you get Okay okay... we'll go with that. The Iron Triangle aka the Project Management Triangle aka the Triple Constraint has been around a long time. The version I first came across was this one. Time, quality and cost. The three parameters are interconnected. Change one and one or both of the other parameters change. I think that makes sense intuitively. For example, if you want to shorten a project, you might Skimp on the quality Throw money at it Skimp on the quality AND throw money at it Things get interesting when we fix one or more of the parameters. My mental model for this is a decorator coming in to do an estimate. looking around the room, Taking some measurements Scratching his chin And saying "I can do Fast, Good, and Cheap." "Which two (pause) would you like " This "pick any two" thing is easier to see if I make the blobs overalp Notice the gap in the middle. This indicates that it's not possible to fix all three parameters. But it IS possible to fix the parameters in pairs. Cheap and Fast ... rush the the job and the Quality will suffer Cheap and Good... is going to take time Fast and Good - which might mean putting more people on the job - will push the price up. And that is all you need to know about the Iron Triangle The three parameters are interdependent You can fix one You can even fix two But you can never fix all three We're ready to move on too apply the Iron Triangle to Waterfall and Agile. And for this there's a variation of the Iron Triangle that's a better fit. It swaps Quality for Scope (Actually, this is the more common version. So if you're going to memorise one of them, memorise this one. OK ) How does the Iron Triangle look for a Waterfall Project Which parameters are fixed, which are variable Let's see if we can figure it out. We're going to build a bridge. It's going to take one year and cost one million dollars cost: $1m time: 1 year scope: 1 bridge What if it costs more money. Not ideal. What if it costs less money. Oh, you'd be okay with that, would you. What if it takes longer than a year. Not great. What if it's complete in 6 months. I'm sure you'd take that. What about Scope How would 3/4 of a bridge work for you What about 1 1/2 bridges You're right: both are silly. We're going to need exactly one bridge So the SCOPE is fixed. In theory anyway, the cost and time parameters are viable for a Waterfall project. it would be remiss of me not to mention that most project managers will CHOOSE to fix a second parameter. Which they choose will depend on what the PM teams to most important: Is time more important Is money more important Let's move on to Agile. It's not immediately obvious that the Iron Triangle applies. For one thing, many Agile projects don't have a crisp start and a crisp end. But I can side-step this problem by picking an arbitrary block of time. Say, three months. Let's look at the parameters Time. That's fixed. 3 months. Cost. Well, if we're talking about a software project, most of the cost of the project team. Agile teams tend to of a more or less fixed size. Fixed team, fixed time. Looks like cost is fixed. Time is fixed, cost is fixed. By the rule of the Iron Triangle this means that the scope must be variable. And that fits with our experience, right And Agile team cannot - indeed should not must not! predict what it will be able to produce in a three month period. They'll start work, they learn, they'll produce. And at the end of the three months, we'll get what we get. Like I said: fixed time, fixed cost, viable scope. There's a rather satisfying symmetry between the Waterfall and Agile Iron Triangles I'll spin this around a bit. Notice that What's fixed for Waterfall is variable