You create a variable called disp:
Which shadows the built-in disp function. From then on:
index into this disp variable instead of calling the disp function. This variable has indeed only 11 elements, whereas
tries to access elements 79, 118, 101, 114 (the character values of 'Over').
Morale of the story: don't use the names of matlab function as variable names. Other common culprits are sum, mean, max, and min.