Introduction:
The given question is about the quality loss of an image due to scaling. In this answer, we will discuss why scaling can cause a decrease in image quality.

Explanation:
Scaling refers to the process of resizing an image. It can be done to make an image smaller or larger. When an image is scaled, its dimensions are altered, which can lead to a loss of quality. Here's why:

1. Pixelation:
When an image is scaled up, the existing pixels are stretched to fit the new dimensions. This can result in pixelation, where the individual pixels become visible, causing a loss of clarity and sharpness in the image.

2. Blurriness:
Scaling an image down can also lead to blurriness. When an image is made smaller, the pixels are compressed, and details may be lost. This can result in a loss of sharpness and a blurred appearance.

3. Aliasing:
Aliasing is another common issue that can occur when an image is scaled. It refers to the jagged edges or stair-step appearance that can be seen in scaled images. This is caused by the limited number of pixels available to represent the image's details.

4. Interpolation:
Interpolation is the process used to fill in the gaps when an image is scaled up. Different interpolation algorithms are used to estimate the colors of the new pixels. However, these estimations may not accurately represent the original image, leading to a loss of quality.

5. Compression artifacts:
If the image being scaled is already compressed (e.g., a JPEG image), the compression artifacts may become more prominent after scaling. These artifacts can include blockiness, noise, and color distortions, further degrading the image quality.

Conclusion:
In conclusion, scaling an image can result in a loss of quality due to pixelation, blurriness, aliasing, interpolation, and compression artifacts. It is important to consider the original image's resolution and the desired outcome when scaling an image to minimize the loss of quality.