A Risky Affair
The figure below shows the long term savings potential of a successful Software Product Line (SPL) over a one-off system development strategy. Since 2/3 to 3/4 of the total lifecycle cost of a long-lived software system is incurred during sustainment (and no, I don’t have any references handy), with an SPL infrastructure in place, patience and discipline (if you have them) literally pay off. Even though short term costs and initial delivery times suffer, cost and time savings start to accrue “sometime” downstream. Of course, if your business only produces small, short-lived products, then implementing an SPL approach is not a very smart strategy.
If you think developing a one-off, software-intensive product is a risky affair, then developing an SPL can seem outright suicidal. If your past history indicates that you suck at one-off development (you do track and reflect upon past schedule/cost/quality metrics as your CMMI-compliant process sez you do, right?), then rejecting all SPL proposals is the only sane thing to do…. because this may happen:
The time is gone, the money is gone, and you’ve got nothing to show for it. D’oh! I hate when that happens.
The Odds May Not Be Ever In Your Favor (Bulldozer.com)
Out Of One, Many (Bulldozer.com)