In moderate amounts, water coming out of your tailpipe can be completely normal and is generally not a cause for concern. Here are some potential reasons why you might see water exiting your exhaust:

1. **Condensation**: After your car has been parked overnight or for an extended period, condensation can form inside the exhaust system. When you start the engine, this water will be expelled as the exhaust system heats up. This is especially common in colder climates.

2. **Combustion Byproduct**: One of the byproducts of combustion in an internal combustion engine is water vapor. Under normal operating conditions, some of this water vapor can condense in the exhaust system and then be pushed out as liquid water.

3. **Catalytic Converter**: Modern cars are equipped with catalytic converters that help reduce the emission of harmful gases. The catalytic converter can also cause some water vapor to condense into liquid water, especially during the initial phases of engine operation.

However, there are scenarios where water coming from the tailpipe could indicate a problem:

1. **Blown Head Gasket**: A blown head gasket can allow coolant to enter the combustion chamber, which could then be expelled through the exhaust as white smoke or water.

2. **Cracked Engine Block or Cylinder Head**: Similar to a blown head gasket, a crack in the engine block or cylinder head can also allow coolant to enter the combustion chamber.

3. **Excessive Engine Idling**: Prolonged periods of idling can lead to water condensation in the exhaust system, which might eventually get expelled as liquid water. If this happens frequently, it might indicate an underlying engine issue.

**How to Tell if There is a Problem:**
- **Color of Exhaust Smoke**: Normal water vapor will generally dissipate quickly and not linger in the air. If you notice continuous white smoke, it could indicate a coolant leak.
- **Fluid Levels**: Monitor your coolant and oil levels. If you find they are consistently low without visible leaks, it could indicate internal leakage.
- **Sweet Smell**: Coolant often has a sweet smell. If you detect this smell coming from the tailpipe, it might suggest that coolant is being burned in the combustion chamber.

**Conclusion**
If you notice moderate amounts of water, especially after starting a cold engine, it is likely normal due to condensation. However, if you observe continuous white smoke, a persistent sweet smell, or you're frequently topping off fluids, it would be wise to investigate further as it might indicate a more serious problem.