Motive is the incitement to an action: emotion, desire, physiological need, or impulse. For example, most murders have one of two motives. The first is money: to collect a life insurance policy or during the course of a robbery. The second is revenge. Killing your spouse's lover, for example.
The legal meaning of intent refers to the state of mind at the time one carries out an action. For example, a person foolishly fires an gun into the air at midnight on New Year's Eve. The bullet kills someone a block away. The shooter isn't guilty of first degree murder, because she did not have the intent to shoot that person (or anyone). They are guilty of a negligent homicide, though, because they did intend to fire a gun with reckless disregard.
The best examples of good motives resulting in criminal action can be found in cases of mercy. Years ago I read the case of a mother charged with neglect because she allowed her terminally ill child to stop taking his chemotherapy. The boy was seventeen (not a little kid), and begged to be allowed to live the remainder of his months without the added pain of the chemo. She argued he should be allowed to make his own decisions. Unfortunately, he died while in state custody in the hospital before the case was resolved. (His mother was there.) The state dropped the charges.
There is a huge difference between motive and intent. Legal cases typically turn on intent, not motive. Here is an example: 'H' and 'J' are having a somewhat tense conversation over a beer and steak at the local pub. 'H' seizes a steak knife and tries to plunge it into J's ribs. Pub regulars overpower him and the police are called. He is charged with assault with a deadly weapon. That’s intent. No one knows H’s motive, but no one needs to know his motive. What he intended was obvious. And it is a crime.
Hope it helps you differ between the two terms.
