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Haris is right in his comment. Using template matching is superb if you have a pretty similar object. You can make it robust to scale by scaling the template up and down (if you have prior knowledge you can bound that to relevant scale values) and rotation by rotating it (again you can bound it intelligently if you have some knowledge of the application). Just keep in mind that in the end, you are repeating the same detection a lot of time so it might be time-consuming, especially if you need real or close to real-time detection.

Where template matching doesn't work well (not every possibilities are listed of course):

• Trying to detect a different kind of arrow (an arrow of a different shape, this would be a case of object class detection);
• Having inconsistent illumination across the scene (if your template uses real pixel intensity value but no relatively illumination invariant methods such as edge detection, etc.)