Why are estimates always wrong?

Douglas Hofstadter nailed it way back in 1979:
"It always takes longer than you expect, even when you take into account Hofstadter's Law."

Sound familiar? 😅

Estimates are notoriously tricky. Here's why:

1️⃣We're overly optimistic. We assume everything will go smoothly. Spoiler alert: it rarely does.
2️⃣We confuse goals with reality. Tom DeMarco put it perfectly:

“If there is no reasonable probability of finishing 20 or 30 percent ahead of schedule—the schedule is a goal, not an estimate.”
3️⃣We lack historical perspective. Without data, it’s guesswork.

So how do we get better at estimating?

✅ Trust your team. They’re the ones doing the work—lean on their experience.
✅ Look to the past. Study similar projects. What actually happened? Use real data to inform your timelines.
✅ Be transparent. Acknowledge uncertainty, build in buffers, and communicate risks early.

Estimation will always involve some unknowns—but we can improve by staying humble, learning from experience, and partnering with our teams.