Gliscor can completely wall some Pokemon, so it can use guillotine repeatedly without worrying about getting hurt. Guillotine's accuracy is 33% when used once, but if you use it 8 times, then its chance to hit becomes greater than 99%.
Also, it's pronounced GIL-o-tine, with a short i sound, short o sound, and long i sound. Don't listen to anyone who tells you otherwise.