quit Quit MATLAB session.
quit terminates MATLAB after running the script FINISH.M,
if it exists. The workspace information will not be saved
unless FINISH.M calls SAVE. If an error occurs while
executing FINISH.M, quitting is cancelled.

quit FORCE can be used to bypass an errant FINISH.M that
will not let you quit.

quit CANCEL can be used in FINISH.M to cancel quitting.
It has no effect anywhere else.

Example
Put the following lines of code in your FINISH.M file to
display a dialog that allows you to cancel quitting.

          button = questdlg('Ready to quit?', ...
                            'Exit Dialog','Yes','No','No');
          switch button
            case 'Yes',
              disp('Exiting MATLAB');
              %Save variables to matlab.mat
              save 
            case 'No',
              quit cancel;
          end

Note: When using Handle Graphics in FINISH.M make sure to use UIWAIT, WAITFOR, or DRAWNOW so that figures are visible.