There are several factors that likely contributed to Saldívar's decision to kill Selena. These include:
* Financial problems: Saldívar was in debt and was embezzling money from Selena's fan club and boutiques to support her lifestyle. She feared that she would be caught and would lose everything, so she killed Selena in order to prevent her from discovering the truth.
* Obsession: Saldívar was obsessed with Selena and viewed her as a rival. She believed that Selena was more successful and popular than she was, and she resented her for it. Saldívar's obsession led her to develop a strong hatred for Selena, which ultimately culminated in her murder.
* Mental illness: Saldívar has been diagnosed with borderline personality disorder, which is a mental illness that can cause symptoms such as impulsivity, mood swings, and difficulty controlling anger. These symptoms may have contributed to Saldívar's decision to kill Selena.
It is important to note that these are just some of the possible factors that may have contributed to Saldívar's decision to kill Selena. It is not clear exactly what motivated her to commit this crime, but it is likely that a combination of these factors played a role.