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12 The PCB Design Magazine • August 2015 fication. We open the door for failure when we have to question orders. But we manufac- turers have to occasionally, when the orders are outside of the guidelines of conventional process or machine capability. Designer and manufacturer communication and respect is key here, and I think this is why Kelly men- tions that it is important that those giving or- ders must be willing to take them if the order would put the part at risk of failure. Shaughnessy: is failure always someone's fault or is it the fault of a bad process, or is it a com- bination of both? Dack: I'm not comfortable pointing fingers at individuals. The causes for success and failure can be attributed to people, but it can also be caused by unforeseen conditions or even acts of God. A good strategy is to identify per - formance requirements and operating condi- tions. The "battle plan" needs to identify con- straints: design constraints, manufacturing constraints, performance constraints, even cost constraints. Knowing the enemy and an- ticipating every possible way a design could possibly fail is crucial, but it can't happen in a vacuum. It must occur through open com- munication with the allies – stakeholders of the product who are connected through the process steps. Thompson: If you're asking if every failure is someone's fault, I would say yes, at the most base level. It will always turn out to be some - one's fault either due to negligence or lack of vigilance. But, as Kelly said, there are extenu- ating circumstances. There can be dynamic situations where environmental, human or mechanical conditions create a failure in the field. Or it could be a poor design type of situation, where something wasn't prop- erly considered in the original de- sign phase. It's a good time to draw in the metaphor of a combat unit here. No one person in a combat unit takes credit for the unit's success or failure. They are a team! Dack: Oh, yes. I like that analogy! A combat unit trains and rehearses their craft to work with other units successfully on the battle - field. A big part of their success is adherence to standards. Standard equipment, weapons and communication is so important! Without standards, orders are non-effective SNAFU. Mentioning standards at this point at least helps to move the question from who failed to how it failed, which is much more impor - tant from a process perspective. Shaughnessy: in your positions, you've both had the experience of seeing a lot of things fail over the years. i wonder if you guys can talk about some of the more prevalent types of failures that you've seen in design and fab. By the way, in our recent survey, we asked our design readers what they thought was the no. 1 cause of failure in the field. a good chunk of the readers said, "sol - der joint failure," and an equal number said, "Bad design techniques." Thompson: I think the survey results are tell- ing. When you ask about what are some of the more common failures in design and fab, and you find that the results vary from bad design to solder failure with a good smatter- ing of both, that really tells you something feature