The eternal developer dilemma: finish a project in 4 hours that management estimated would take 6 months. Do you reveal your wizardry and risk getting more work dumped on you? Or do you quietly sip coffee for the next 5 months while occasionally muttering "it's more complex than it looks"?
This is why estimation meetings exist—so developers can pad timelines by 800% while managers nod knowingly. The remaining 19% of the project is just documentation no one will read anyway.
Pro tip: Always save some trivial feature for the last week so you can heroically "finish early" without revealing you've been playing Minecraft for five months.