[jconley]

Same experience here. Been writing code for over 20 years. There's a reason we don't do big Waterfall projects any more. No amount of research uncovers all requirements. In the real world, with the ease of refactoring in powerful IDE's these days, there is no reason to spend too much time thinking about a small problem like those presented for whiteboard coding.

In practice, in an interview, this is the wrong approach. I've failed interviews for this as well.

Most of what differentiates a Senior Engineer is communication, mentorship, ability to compromise on product requirements, set realistic expectations, design solutions to big problems, think in the large and hold the whole system in their head, design API's, things like that.

I no longer do interviews that require me to write code. They're just ridiculous for the type of skills I'd hope a company would value in a Senior Engineer.