Tag Archives: michael-wolfe

Why Software Development Estimation is Hard: Sea Lions, and Coastal Paths

Among the many val­id responses to the Quora ques­tion of why soft­ware devel­op­ment task estim­a­tions are often off by a factor of 2–3, Michael Wolfe, CEO of Pipe­wise, describes exactly why this is without once men­tion­ing ‘soft­ware’ or ‘pro­ject’.

Instead, Wolfe elo­quently provides undoubtedly the best ana­logy I’ve ever heard for explain­ing the dif­fi­culty in provid­ing estim­ates for soft­ware pro­jects: a couple of friends plan­ning a coastal hike from San Fran­cisco to Los Angeles and start­ing their jour­ney.

Their friends are wait­ing in LA, phone calls have already been made push­ing the date back…

Man, this is slow going! Sand, water, stairs, creeks, angry sea lions! We are walk­ing at most 2 miles per hour, half as fast as we wanted. We can either start walk­ing 20 hours per day, or we can push our friends out anoth­er week. OK, let’s split the dif­fer­ence: we’ll walk 12 hours per day and push our friends out til the fol­low­ing week­end. We call them and delay din­ner until the fol­low­ing Sunday. They are a little peeved but say OK, we’ll see you then. […]

We get up the next morn­ing, band­age up our feet and get going. We turn a corner. Shit! What’s this?

God­damn map doesn’t show this shit!. We have to walk 3 miles inland, around some fenced-off, fed­er­ally-pro­tec­ted land, get lost twice, then make it back to the coast around noon. Most of the day gone for one mile of pro­gress. OK, we are *not* call­ing our friends to push back again. We walk until mid­night to try to catch up and get back on sched­ule.

Of course, this isn’t exactly a new ana­logy: it’s apply­ing the ideas behind Benoît Mandelbrot’s paper, How Long Is the Coast of Bri­tain?, pub­lished back in 1967, to soft­ware estim­a­tion. Still, it works per­fectly.

If you like Wolfe’s writ­ing style and want to read more, he runs a blog called Dear Founder.

Update: And of course, there’s always O.P.C.