Malbim: Not saving is due to one of three reasons. (a) It is not the giver's nature to do good. You are "Tov v'Salach"! Also refer to 86:5:2:3, 86:5:3:2.

Radak: He is Tov to all His creations - "Tov Hashem la'Kol" (145:9). He is Salach to sinners.

Radak citing Shocher Tov: Why is He Tov? Because He is Sole'ach. Why is He Sole'ach? Because He is Tov.

Malbim: It is even to sinners. (Therefore, You should not refrain from saving me due to my sins.)

Radak: It is to all who call to You amidst their afflictions. Even if they did evil, since they return to You at the time of their afflictions, You give "Rav Chesed" to them. All the more so You should do so to me!

Malbim: One might refrain from saving based on the connection to the recipient. If the giver gives only based on the recipient's deeds, perhaps I am not worthy. However, You are "Rav Chesed l'Chol Kor'echa" - You give without looking at the recipient's deeds!