I was working on something for 5 days from a requirement, extremely satisfied with the results.

The boss comes over to see what I've done and says it's not what they expected.

The requirement was poorly written because what he said compared to what was written is two different things.

Tip: Share the work and the code you've produced (at least inform) to make sure you are on the right path. There is always a gap between a requirement and what the stakeholder actually wants.