So can your eye sight be too bad for lasik?

Yes: There are many people who should not have lasik surgery, e.g., far-sightedness, wide pupils, dry eyes. In general one should refrain from surgery for disorders that can be treated otherwise.

Yes: Severe nearsightedness, farsightedness, cataracts, thin cornea and abnormal corneal shape.

Yes: Laser eye surgery can typically correct from +5 to -10 d as long as everything else is normal. If you prescription is outside this range, then you may not be able to correct your vision.