If a dog is not quickly dried after bathing, there could be some adverse effects, including:

1. **Skin Problems**: Prolonged exposure of wet fur to the skin can lead to the growth of bacteria and fungi, increasing the risk of skin infections and inflammation, especially for dogs prone to skin conditions.

2. **Hair Issues**: Wet fur is prone to tangling and matting, leading to unpleasant odors, increased shedding, or even skin problems over time.

3. **Odor Concerns**: Wet fur can develop unpleasant odors over time, causing discomfort for the dog and unpleasant smells in the household.

4. **Health Risks**: A damp fur and skin environment can facilitate the growth of bacteria and parasites, increasing the risk of illness for the dog, especially in cold or humid conditions.

Therefore, to avoid these issues, it's best to use a hair dryer to quickly dry a dog's fur after bathing, maintaining their skin and fur cleanliness and health.