If Mark was dependent on Luke, then why would Mark exclude the Q material from Luke?

If Mark had access to Luke, and his edition of Luke already included the so-called "Q material," how can we reasonably explain his failure to include that material in his Gospel?

My question is asked more fully here:

https://donaldtraxlerpoetry.blogspot.com/2023/03/synoptica-xxxvi-about-luke.html