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Shift Left Is the Tip of the Iceberg

(semiengineering.com)
172 points yatrios | 2 comments | 19 Nov 24 14:06 UTC | HN request time: 0s | source
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0xbadcafebee ◴[19 Nov 24 15:15 UTC] No.42184298[source]▶
For those not aware, Shift Left[1] is (at this point) an old term that was coined for a specific use case, but now refers to a general concept. The concept is that, if you do needed things earlier in a product cycle, it will end up reducing your expense and time in the long run, even if it seems like it's taking longer for you to "get somewhere" earlier on. I think this[2] article is a good no-nonsense explainer for "Why Shift Left?".

[1] https://en.wikipedia.org/wiki/Shift-left_testing [2] https://www.dynatrace.com/news/blog/what-is-shift-left-and-w...

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coryrc ◴[19 Nov 24 18:55 UTC] No.42186878[source]▶
No evidence most of the activities actually save money with modern ways of delivering software (or even ancient ways of delivering software; I looked back and the IBM study showing increasing costs for finding bugs later in the pipeline was actually made up data!)
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1. 1propionyl ◴[19 Nov 24 20:44 UTC] No.42187893[source]▶
Are you referring to the IBM Systems Science claims (likely apocryphal) in the Pressman paper, or Barry Boehm's figure in "Software Engineering" 1976 paper which did include some IBM sourcing (literally drawn on) but was primarily based on survey data from within TRW?

It baffles me that anyone would continue to promulgate the Pressman numbers (which claim ~exponential growth in cost) based on... it's not entirely clear what data, as opposed to Boehm's paper which only claims a linear relative cost increase, but is far more credible.

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2. coryrc ◴[20 Nov 24 00:16 UTC] No.42189508[source]▶
Pressman i.e. https://www.theregister.com/2021/07/22/bugs_expense_bs/

In a waterfall, single-deliverable model it wouldn't surprise me there is some increase in costs the later a bug is discovered, but if you're in that world you have more obvious problems to tackle.

People still use the Pressman numbers. So much for "data-driven decision making"...