I would say that it is possible for a person’s attitude to become too positive to the point where it starts to have negative impacts. Here are a few ways that an overly positive attitude could potentially affect decision-making:

1. Unrealistic Optimism: An excessively positive outlook can lead someone to have unrealistic expectations and underestimate the risks or challenges they may face. This could result in them making poor decisions by not adequately preparing for potential setbacks or obstacles.
2. Lack of Critical Thinking: When someone is overly positive, they may become less inclined to engage in critical analysis and consider alternate perspectives. This could make them blindly optimistic and prevent them from seeing potential downsides or flaws in their plans.
3. Dismissal of Negative Feedback: A very positive person may be quick to dismiss or downplay negative feedback, even if it contains valid concerns or constructive criticism. This can hinder their ability to learn and improve.
4. Overconfidence: Extreme positivity can foster a sense of overconfidence, leading someone to take on more risk than is prudent or make decisions without adequate caution or preparation.
5. Difficulty Adapting: If someone’s positivity is inflexible, it may make it harder for them to adapt their approach or change course when circumstances require it. They may stubbornly cling to their original, overly positive plan.

That said, it’s important to note that a generally positive attitude can also have many benefits, such as increased motivation, resilience, and ability to see opportunities. The key is finding a balanced and realistic approach that allows for appropriate consideration of both positive and negative factors.