ECOs are stupid II: The price of unincorporated change
The venerable Engineering Change Order (ECO) has certainly had its day in the opulent halls of classical change management, but thanks to technology, ECOs might very well be on the path to extinction. Last time we mentioned that ECOs are slow and stupid, we emphasized that reducing overall ECO cost involves more than just reducing avoidable change. The second half of that battle involves the change process itself, evolving it to be both more agile and effective. Protip: It’s all about addressing the weaknesses of unincorporated change.
The whole “unincorporated change” thing
But just what is this unincorporated change thing, anyway? The traditional engineering change process details new changes on separate documentation including the rationale behind the change. The ECO follows its own lifecycle and stands as a permanent attachment to the design record until the changes are fully incorporated into the original design documentation at a later date. Until that future incorporation, the ECO stands in conjunction with the original design to represent the changed design record. It’s official documentation, yet is still a separate attachment, hence the term “unincorporated.”
OK, so that’s just fabulous – why is unincorporated change necessary, why can’t you just make the change directly to the design?
How we got stuck with the limitations of the past
The concept of an unincorporated change was a necessary compromise in the past because of limitations in changing design data, especially in the era of manual drawings and early CAD, when drawing views didn’t just update with a click or two. Understanding the difference from one version of a design to another chiefly involved intense staring for prolonged periods of time until the change was understood and/or blindness occurred. To minimize eye strain, ECOs often highlighted the changes specifically, sometimes with designation of WAS/NOW views side by side on the form. As in now-now, not then, which, ironically, would be incorporated soon.
That was then and this is now
So if design changes today can be applied with a click of a button, why does the original ECO approach persist? Perception is that the ECO is a faster process, even though –technically– such a change should be subject to the very same approvals to enact as a normal drawing revision. But often the spirit of ECO “fastness” prevails and many companies internally foster a bit of a double standard when it comes to change approval. Especially if the change is marked “hot” (one of the most abused modifiers in engineering history) with some bright colors or some menacing stamp, and then everything’s suddenly fair game in ramming the change through the system. But hey, you got the change out, right?
Unincorporated change has a price
What few realize is that unincorporated change suffers from several problems that offset any release turnaround advantage:
When an ECO change is finally reincorporated, chances are whoever is tasked with that job is not familiar with the change and may interpret it incorrectly (especially if several changes were stacked together), introducing error. This is especially troublesome with changes which cancel other changes. ECOs can’t be dependent on other ECOs. They must stand alone. So a redo of a redo cancels the original.
But you also don’t want to cancel an ECO that cancels another ECO for reasons concerning your own sanity and sound configuration control. The confusion involved can be overwhelming, and is the reason most change processes also reasonably limit the number of unincorporated changes that can be attached to any one particular design.
The most damaging penalty of unincorporated change is the interpretation cost of that attached change throughout the life of that particular design. Anyone who has seen a drawing with unincorporated changes stapled to it and highlighting or red marks everywhere (or the digital equivalent thereof) are quite familiar with that cost.
The problem is that interpretation cost occurs each and every time someone has to look at the design. Not just the engineer, but everyone. Even if the ECO is fully electronic, you have to go fetch and view that record separately; you have to open two things and not one.
Obscured design intent:
A key advantage to the ECO is recording rationale for design intent, i.e. understanding why the change occurred. The trouble is, in most cases this information becomes obscured upon incorporation. The typical revision history on the new version might read “incorporated ECO X”.
So if you come in after the fact, and wonder why the revision happened to begin with, guess what you have to dig up that ECO. And while a good management system will allow you to find the link and then open it separately. It’s not cohesive. It’s old school.
Time to simplify, man
There’s value and compactness in introducing change directly into a full revision and relying on the expanding repertoire of comparison technologies to quickly understand differences between subsequent models and layouts, or even an entire history all at once. In more complex workflows, however, this can get tripped up a bit when you have multiple out of sequence changes, but that’s something we will talk about another time – which is how the linearity of engineering change is about to go away.
While you think about that, I have drawn up this new ECO for you to sign which cancels the one I showed you yesterday. This one is double-hot-turbo-EX-alpha-plus-with-a-cherry-on-top-and-a-side-of-fries. If you could sign it in the next five minutes without staring at it to the point of blindness, I’d really appreciate it.
About the author: (Ed Lopategui)
Technology evangelist, entrepreneur, and aerospace engineer specialized in the software tools and technology which enable engineering, design, and product development - PDM, PLM, CAD, CAE, CAM. Any views, opinions, prophecies, and sarcastic remarks are my own and are in no way associated with any current or past employers.
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