Credit: ABC Family

The Season 4 finale of Pretty Little Liars included a last-minute shocker: Mrs. DiLaurentis dead in a ditch as someone – presumably “A” – buried her. Why would he or she kill Mrs. D.? We speculate below.

“A” wanted to punish Ali

“A” tried to kill Alison in the Season 4 finale, and failed due to Ezra’s desperate ninja skills. Perhaps, he or she found another way to punish Ali: by killing her mother. This is super harsh, we know, but “A” seems to be getting more and more desperate. With Mrs. DiLaurentis dead, Ali becomes even more isolated. She still has the Liars, but her family has been destroyed. It will never be made whole again, even if Ali does unmask her harasser.

To punish Mrs. D. for burying Ali alive

Last night, the truth about what happened to Ali the night of her disappearance came out. She was knocked out by someone, then buried alive by her mother who wasn’t aware Ali was still breathing. Was “A” listening in on this confession? Did “A” take it upon him/herself to punish Mrs. D. for what she unknowingly did to Ali? This seems a little counterintuitive, but we’re still not sure why “A” is tracking Ali. Perhaps, “A” wants her for him/herself. Perhaps, he or she wants to be the only one who can punish Ali. Twisted, but possible.

Mrs. D. knows who “A” is

Mrs. DiLaurentis knew much more than she let on. Top of the list: who knocked Ali out that night. It was someone she was willing to protect, but apparently not someone who was willing to protect her back. Did “A” kill Mrs. D. so that she could never tell anyone the truth about the night Ali almost died?

To keep the Radley secret safe

The identity of “A” isn’t the only secret being kept in Rosewood. There’s also whatever Radley is hiding left to uncover. Sure, we think they’re related, but was Mrs. D. killed for the latter rather than the former? She was on the Board of Directors at Radley, and might have been talking to the sanitarium the night Ali went missing. She had multiple official-sounding phone calls that seriously stressed her out and prompted her to worry about Ali’s safety, telling her daughter to stay in for the night. Did “A” kill Mrs. D. to keep whatever Radley is hiding a secret? With Ali’s return, was he or she worried that Mrs. D. was about to tell?

Why do you think “A” killed Mrs. DiLaurentis? Share your theories in the comments below!

Catch the next episode of Pretty Little Liars on June 10, 2014 at 8 p.m. ET on ABC.

Kayti Burt is a contributing writer for Wetpaint Entertainment with a penchant for all things pop culture. Follow her on Twitter and Google+!