What could be a sign that a power tool is not suitable for a task?

Strain during operation serves as a significant indicator that a power tool may not be suitable for a particular task. Tools should be designed for user comfort and efficiency; if a tool causes strain, it may not be well-matched to the job at hand or could potentially be a poor-quality tool. Experiencing strain while using a tool can lead to decreased productivity, increased risk of injury, and the possibility of not achieving the desired results. Proper tool fit and ergonomics are essential for effective and safe operation, and any discomfort signals that one should reconsider the tool's appropriateness for the task.

The other options do not directly correlate with the effectiveness or suitability of the tool for a specific application. A bright color scheme or being on sale might be appealing or a marketing tactic, but they don’t influence the practical performance or suitability of the tool. Similarly, while the model's recency could suggest advancements, it doesn’t guarantee suitability for every specific task. The focus on user experience and comfort is crucial, making strain a key sign to evaluate when selecting power tools for any job.