Define "motive." Do you mean, for example, some comprehensible reason? Many assassins are mentally unhinged. Their motivations are subjective and often don't make sense. They don't act or think like rational people which is why they are assassins. Did John Hinckley have a motive to assassinate Reagan or was he just a nut acting out some bizarre fantasy? Oswald falls in the latter category. A nut with an image of himself as some type of revolutionary figure. Thus, the BY pictures and attempt to gain entry to Cuba. Willing to die to be remembered in the history books. It doesn't have to make sense because it can't. It is the act of a mental case. We don't have to know or agree about his motive, however, to conclude he is the guilty party. And the reasons don't have to make any sense to a rational person because a rational person wouldn't act as he did. It's the evidence that informs us of his guilt.
Oswald falls in the latter category. A nut with an image of himself as some type of revolutionary figure. So you think he was yelling to reporters...."I got him,....He was a threat to communists and I got him" Just ignore the fact that the right wingers ( American Nazis)were convinced that JFK was a "commie symp"
BTW.... Can you present just one personal statement of Lee Oswald in which he proudly admits the murder, and proclaims his greatness? If you can't ... then there's a very strong probability that you're living in La La Land.....or have been smokin somthin.