Shift Left Is the Tip of the Iceberg

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...

So “shift left” is roughly equivalent to “tests first” or “TDD”?

It can also mean manual testing earlier. Valve credits playtesting early and playtesting often for their success with Half-Life, Half-Life 2, and other games.