Final answer:
If pate a choux dough is too wet, it will spread out and fail to rise properly during baking, resulting in dense pastry without the characteristic hollow center.
Step-by-step explanation:
When pate a choux dough is too wet, it can cause numerous issues during the cooking process. Ideally, pate a choux dough should be thick enough to hold its shape when piped onto a baking sheet. If the dough is too wet, it may spread out too much before or during baking and fail to rise properly. This happens because the excess moisture will turn into steam, but if the dough cannot trap this steam effectively due to its runny consistency, it won't puff up as it should. The resulting choux pastry may be overly dense, rather than light and airy, and it might not develop the characteristic hollow center. To fix a wet dough, more flour can be added to reach the correct consistency before baking.