Comment by wjnc | Hacker News Reader

Comment by wjnc | Hacker News Reader

Parent Full thread

In the Toyota / lean-theory rework is the start of an near-exponential process where different tasks are waiting for the other to be completed ad infinitum. If you've ever worked at an old-school firm you'll recognize this: the quality of your input, a colleagues output (say, a dataset) is sub-par, so you start checking it regularly. If it falls short to your standards, you ask for a new set and wait. He does his work again, and you restart your task and start checking his work even before you start your real work. That's a lot of time ill spent.

Multiply that over departments and many processes and the result is great inefficiency. So FPY is the KPI to stop all that. FPY is not really valuable by itself, but hopefully by the culture it supports. Swapping FPY for # delivered is false management and points to cultural issues. In this case: managing by the wrong target (# delivered instead of the "total worth of the value chain").

Nobody would care if Tesla would just deliver growing amounts of cars at falling costs. It's the bootstrapping (in the Baron of M-sense) towards false metrics that gets the poison going and management is totally working within that frame of mind. They should find their own frame, and operational excellence just might be one. (Apologies for the MBA bs-bingo, but in this case I think it's to the point.)

Telsa really should aspire to Toyota levels of efficiency, but you also have to account for the fact that Toyota has had decades of experience as well as a stable and long-term relationship with their parts suppliers. Stopping the line and reconfiguring that plant in a Toyota plant is likely a minor rework for efficiency. But when a model and line and entire system is all new, a stoppage might not be a small rework despite best efforts to have arranged for it to be so ahead of time. Even the timeline and difficulty to setup a new Toyota plant vs a new Tesla plant aren't really comparable, because Toyota also has and excellent and stable set of design practices and supplier relationships. If two to three years from now, the rework ratio hasn't dropped considerably then Tesla is doing something wrong, but right now I think it's understandable that Tesla is just getting on it's legs wrt truly mass production. You always have to learn new things at each order of magnitude of production - even with products and methods that have been successful at the previous production level.

A thought: We're at a point in time where Toyota employees and management (and many other manufacturers' employees and management) have that experience. This experience is not something that has to be learned with every new iteration of the car production line - it's something that can quite literally be bought.

The question that follows on: What internal process has prevented that experience from being bought? Instead Tesla seems to have opted to gain that experience from scratch at great cost to investors (and consumers).

Some expertise can be bought, but some of the support is built over time, intrinsically outside the factory into the overall Toyota system. But ironically, thinking one can just buy an expert is to apply the same short-term mentality to the process that Tesla is accused of misapplying to product.

When Toyota first started creating their own US factories, they took the steps of shipping floor employees in the US to japan a few at a time and working for weeks of training each class. When other auto companies tried to replicate Toyota processes in their own factories, it didn't help yield in the factories in many cases because often the input supplies needed so much rework. And then they had problems changing suppliers configurations because those relationships were contentious, and not of the nature of Toyota to it's suppliers. When you're trying to stand the whole system up at once, it's not just a matter of "don't write bugs" in one part of the final assembly.

When Boeing reworked it's production design process for the 787, they had years of production problems to re-iron out, despite having years of great process experience previously.

The problem here seems to be that they seem to be striving for significantly short term goals, like meeting production targets, rather than really doing the work change the entire system and culture to one that would focus more on quality.

That doesn't really bode well for their future if they consider their current production rates that imminently important to their success.

But who is going to give them money to shut down the production line again and retool everything to increase FPY? And will they do it again when more issues are found?

Isn't swapping FPY for # delivered while they determine the root of the issue and fix it a good plan? It keeps the money flowing in, it helps them find other issues in parallel, and keeps cars getting delivered.

I see a lot of people critisizing Tesla here, but my question is what would you do? You are already in a situation where your plant is producing cars with flaws, no pretending that you don't make mistakes or are infallible and would never be there.

Garbage is flying off the line, what is the solution that you would go with that is better than what Tesla is currently doing?

Agree. FPY might not be the metric fitting the current status of the company best. It's all situation-dependent. FPY of 14% is clearly unsustainable though. That's because quality is not one or zero, but a continuum. So what's the SPY, TPY, etc.

Yeah, i'd love to hear final numbers on how many have issues once in the hands of customers, or what kind of issues they are fixing, or how long they plan on having this "manual" patch in place.

Without that information, it seems kind of silly seeing everyone proclaim how Tesla is done because of this... It's like telling your doctor that you don't want the medicine because the better solution is to just never get sick in the first place... yeah, everyone agrees, but you are sick, so here take this.

> But who is going to give them money to shut down the production line again and retool everything to increase FPY?

I imagine that it's significantly cheaper to fix the problem (and identify a root cause) when the car is still in pieces than to disassemble the finished product to fix the problem.

As for re-tooling, that can be done down the line with a manual fix in place in the short term (after all, they're able to fix it manually after the assembly line is completed).

Much like how in software development it's cheaper and faster to fix a bug caught in development than it is in production.

Yes, but if you find a bug in development and you are days away from shipping, and you have a solution that fixes the problem but doesn't address the root cause, are you going to delay the whole launch so you can fix it before hand? or are you going to release with the patch, and fix the root cause later?

Now software is different than cars, but I'm gonna say that I'd go for the latter just about every time. Both as a developer, and as a user.

Reply on news.ycombinator.com