Story points are not a tool for duration, they are a tool for relative estimation and should never be converted to time in any capacity. _Especially_ not inter-team.
This is the current biggest mistake in the industry, imo.
I agree, but I'd say story points are themselves a mistake. In the end, what matters is time. Story points don't matter if the schedule slips. So you either get story points and no way to keep a schedule, or story points + time estimates (with useless story points), or just go with time estimates.
The schedule may still slip, since estimating time is very difficult, but at least some of the time it will be correct (or estimates will get padded until things happen on time). Either way, it's more useful than giving up on the problem.
The entire purpose of introducing story points is to move away from time estimating. Time estimating is broken and inaccurate. Complexity estimating is marginally more accurate but still with a wide range of inaccuracy.
Instead teams should focus on delivering value incrementally, then using metrics over those increments as a measure for future increments.
And yet there's still a product, still a date that product will ship to customers, and therefore time estimation is at some level necessary. Often there's a factory building something, physical shipping, late fees, etc. If you're solely responsible for setting all your own deadlines, then there's no need to estimate time. That's very rare.
Time estimating is broken and inaccurate. But that doesn't mean it's unnecessary, or that one can just give up on it. Teams should focus on delivering value incrementally, then using time taken as a metric (among others) over those increments as a measure for future increments.
Hence my point about using measurements from historic actuals to give a forecast instead of asking for explicit estimates. Sitting some devs down and asking them for gut feels is far less accurate than comparing to previous increments.
Certainly! "Gut feel" is a shit way to do time estimates. It's a programmer way, not an engineering way. Of course it's harder to get historical data for software than for other engineering fields, because software is so new. But it's not impossible, and if companies don't even collect the data (due to using story points) they'll never manage to get forecasts when they need them.
In my experience, points are more accurate than hours, since most people work with high variability in productivity over time that can't be captured by a mechanism as crude as a stopwatch, so a corollary metric creates a more accurate number than an absolute metric.
Yah exactly. A scrum master will also say never try to equate points to hours, its a losing game.
But being able to look back in May and say we logged 32% of all development hours on bugs is a very useful metric for me the business owner / dev lead.
(In addition we don't do story points on bugs. I am so far away from the by the book agile thing, I don't even know if this is correct or not anymore).
This is the current biggest mistake in the industry, imo.