Too much water can lead to a condition known as damping-off. This condition kills off young seedlings but is easily preventable by planting disease-resistant seeds and allowing soil to dry out between waterings.
One possible result of too much water is the cessation of budding. Since cucumbers naturally have periods of high-bud and no-bud, this occurrence would only be of concern if an otherwise healthy plant at its early stage of growth, stops flowering.
A more common result of overwatering is yellowing fruit. Unless you've planted a variety that grows yellow, your cucumbers should be green. However, overwatering is not the only cause of yellowed fruit. Some viruses and an improper soil nutrient balance can also cause yellowing.
Sopping soil can lead to an array of conditions that can damage and kill a crop. Fungus grows and disease spreads in moist, damp environments. Likewise, damaging slugs and snails thrive on too much moisture.
Cucumbers require 1 inch of water per week; too much or too little can stress the plant and its growth. They grow deep root systems and should be watered only at their base. Use a slow trickle of water and allow the soil to dry between watering. Avoid intentional water contact with the plant's foliage.