Por qué has

why have you

→ por
phrase Common #5,884
why have you Usually followed by a past participle to ask why someone has done or experienced something.
SP: ¿Por qué has llegado tan tarde?
EN: Why have you arrived so late?

¿Por qué has vaciado la botella?

Why did you empty the bottle?

— Stalker (1979)

¿Por qué has esperado tanto?

Why have you waited so long?

¿Por qué has escogido esa flor?

Why did you choose that flower?

— Summertime (1955)

¿Por qué has apagado la luz?

Why did you turn off the light?

¿Por qué has rechazado su oferta?

Why did you turn down their offer?

¿Por qué has cerrado por dentro?

Why did you lock it from the inside?

— Tesis (1996)

¿Por qué has aplazado el ir al dentista?

Why have you put off going to the dentist?

¿Por qué has tardado tanto?

Why have you taken so long?

— Escondido (2005)

¿Por qué has esperado diez años para buscarme?

Why did you wait ten years to look for me?

— 三峡好人 (2006)

¿Por qué has pintado de rojo el banco?

Why did you paint the bench red?

¿Por qué has arruinado nuestro plan?

Why did you ruin our plan?

— 암살 (2015)