Some have alleged that since Mark's Gospel is the earliest of the four, and it doesn't contain a narrative of the disciples seeing a bodily resurrected Jesus, that the later Gospels that do narrate such post-mortem appearance are later legendary developments. Apart from the fact that 1 Cor. 15:3-8 predates the pre-Markan passion source, and that when you compare this early Creed with the Sermons of the Acts of the Apostles on the one hand, and the Gospel narratives on the other, we see that the bodily appearances in the Gospel correspond like an outline with these earlier creedal formulas thereby confirming that they weren't later legendary developments not to mention several other reasons for rejecting the 'legendary' hypothesis for the physical appearances of Jesus, it simply fails to consider a better explanation for Mark's abrupt ending that has to do with the theology of Mark rather than an account that is denying physical appearances of Jesus. Indeed, the Gospel of Mark anticipates and mentions that there would be such appearances anyway! In any case, the following article does a splendid job of surveying possible theological motivations Mark probably had for ending his Gospel the way he did concluding that "The most satisfying viewpoint is that Mark concludes his Gospel by juxtaposing promise and failure. The prediction of 16:7 implies a promise that a restoration to discipleship is available in spite of failure, while the disobedience of the women in 16:8 serves as a warning that failure is possible even after the resurrection."