[nabilhat]

It's a design error from the start. The workaround shouldn't have happened, but is only one of countless ways this would have inevitably happened anyway. Glue has a lot of failure modes. Correct application can't be reliably tested non-destructively. Product variances are often very hard to detect. Degradation with age and physical use can't be reliably forecast.

Three pins on the back of that appearance plate that push into starlock style fasteners in the pedal are cheaper than the appropriate glue, faster to install than glue, more reliable, trivially verified, impossible to misalign, and that's why it's a common solution that auto manufacturers use in this exact application. This was a confoundingly stupid place to rely on glue.

[Draiken]

This is an underrated point. A lot of focus has been put on manufacturing procedures when this could've been avoided entirely in design.

IDK anything about manufacturing so I wonder if this was due to incompetence, to save costs, ignorance or something else?

[sonicanatidae]

Why not all of the above?

[FredPret]

Correct - a great design is also easy / automatic to build correctly. This is vastly easier said than done when you have a complex product with many components.

I remember reading about the original iPhone's manufacturing operations in China - how the Apple engineers spent a ton of time making sure that the right way is also the easy way for the factory workers.