Possible scenario:
Tech problem, aircraft returns to gate - delay, duty time, industrial situation distracting crew etc etc...
Fault in aircraft warning systems but departure allowed.
Taxy out for second attempt, rushed procedures, before takeoff check not performed, aircraft attempts take-off with slats and flaps retracted...
Unlikely? It's happened before - Northwest MD82 N312RC Detroit 16th August 1987.
Sorry don't know how to post a link to the NTSB report for the above.