Most of these are not silly ideas. They are reasonable-sounding rules that happen to work against dry skin, and most of us absorbed them without ever being told them directly.
1. Clean skin should feel squeaky
That tight, squeaky feeling is not a sign of cleanliness. It is what a surface feels like once its oil layer has been removed.
Skin that feels comfortable and unremarkable after washing is the better outcome. Boring is the goal.
2. Hotter water cleans better
Hot water is very good at removing oil, which is exactly the problem. Warm is enough for getting clean, and it takes far less with it.
Long hot showers feel wonderful and are one of the most common reasons skin is drier in winter than it needs to be.
3. Dry skin should be left to breathe
Skin does not breathe. It exchanges nothing meaningful with the air, and leaving a dry patch uncovered does not help it recover.
What dry skin needs is moisture and something to slow the moisture leaving again. Doing nothing is not a neutral choice.
4. Thicker is always better
For a specific rough patch, a rich balm genuinely is the right tool. As an all-over daily product it is usually the reason people give up.
The moisturizer that works is the one you keep using. Weight and absorption matter more than richness.
5. You can skip moisturizer in summer
Air conditioning, chlorine, salt water, sun and more frequent washing all pull in the same direction. Summer is different from winter, not easier.
6. If it stings, it is working
Stinging is not evidence of effectiveness. It is a signal to stop using the product and see whether things settle.
Introduce one new product at a time so that when something does not agree with you, you know which one it was.
7. A routine has to be complicated
Nine products is a project, not a routine. Cleanse, hydrate, and give extra attention to the worst areas. Three steps is the version people actually keep up.
One thing that is not a myth
If your skin is not settling, or it is getting worse rather than better, that is a conversation with a doctor or a dermatologist. Nothing here is medical advice, and no skincare routine is a substitute for one.
Where to start
The three-step version is Cleanse, Hydrate and Nourish. If you want the short explanation of what each step is for, it is here.