1 Poor quality of the Mirror
Looking yourself in a poor quality mirror or if it is in bad condition might not able to show you a perfect reflection of you.
2 The angle of Mirror
Let's suppose you see yourself from a window, which means you are looking for yourself from a completely different angle. It can result in making a perception in your mind that you are looking ugly, but in reality, you are not! See also Why do I look Ugly in Videos?
3 Lighting is a significant variable
If you are looking at yourself in a saloon's Mirror, you may see your enhanced image because of the immense lighting. Hence, lighting is considered a significant factor that can make you look ugly if it is unfavorable. See also why we like familiarity.
4 Looking yourself from a distance
If you are standing far off from the Mirror, you may experience your reflection to be unfamiliar and hence, ugly.
5 The size of the Mirror
We might be familiar with the Mirror of the specific size in which we see our reflection. However, we may find our image unattractive in a tiny Mirror.
6 Sunlight effective
The image we see of ourselves at home may differ from the one we see in our car and their side mirrors. We notice this difference because of the sunlight changes how we look.
7 The dirt of the Mirror
You might see your image as distorted or ugly if the Mirror is covered with grime.