1. Psychological factors: When you look in the mirror at home, you may feel more confident and comfortable, which may make you look better in the mirror. You may feel more nervous and uncomfortable in front of the big mirror in the shop, which may make you look bad in the mirror.

2. Angle and distance of the mirror: When looking in the mirror at home, the angle and distance of the mirror may be more suitable for your five senses, thus making you look better in the mirror. In front of the big mirror in the shop, the angle and distance of the mirror may not suit your five senses, making you look bad in the mirror.

3. Lighting: When you look in the mirror at home, the indoor lighting may be softer and more uniform. This lighting condition can make your facial features more prominent, thus making you look better in the mirror. In front of the big mirror in the shop, the lighting conditions may be uneven, which may make your facial features less prominent, thus making you look less beautiful in the mirror.

4. Personal habits: Looking in the mirror at home may be that you are used to your five senses and your own image, so that you can look better in the mirror. In front of the big mirror in the shop, you may not be used to your side face, so it doesn't look good in the mirror.

To overcome this sense of inferiority, you can try the following methods:

1. Adjust your mind: try to keep a confident and peaceful mind and don't care too much about your appearance.

2. Adjust the angle and distance of the mirror: When trying on in the store, you can try to adjust the angle and distance of the mirror to find the one that suits you.

3. Pay attention to lighting: When trying on in the store, you can try to choose a location with better lighting conditions to make yourself look better in the mirror.

4. Accept your appearance: Try to accept your appearance, don't pursue perfection too much, and believe in your internal advantages.