Why did the Sagrada Família take 144 years to build?

[김형수(농학과24)]

Why did the Sagrada Família take 144 years to build?

https://www.youtube.com/watch?v=k6YZCnlEnGE

The Sagrada Familia explodes with light: the stunning performance Pope Leo witnessed in Barcelona

https://www.youtube.com/watch?v=I_-lGSGOi8I