What about secret homemade products without an ingredients-listing?

Paying homage to Fan Bing Bing's beauty secret of using 700 facial masks a year, homemade skincare products has begun its newest wave on the market. Besides getting to feel like a "scientist", homemade products can be natural, with no preservatives, in any form of fragrance in accordance to personal preferences and you'd be saving a whole lot of money (or you could even jump on the bandwagon and start operating your own business). It really is a fad that serves multiple purposes.
The most commonly available skincare products on the market are now widely propagated using terms such as "Homemade Family Recipes", "Secret Ancestry Formulations" using a verity of herbs, flora and fauna, et cetera. Some have even gone to the extent of purchasing raw materials for self-production at home- it's not only low in cost, but they could pretty much make it work in whatever way they'd like.
Thus, if secret homemade family formulations sold online for a low price are that effective, then wouldn't it have already caused the downfall of numerous pharmaceutics, beauty and skincare giants around the world? So to all our beloved readers, please beware of the legendary "secret formulation" skincare products that come without an ingredient-label nor proper verification from the appropriate health sciences authorities.
A three-pointer guide has been introduced to evaluate what makes a skincare product dependable and credible. They are first and foremost, SAFE, EFFECTIVE, PRACTICAL, with safety topping the charts of what people do prioritise in their daily lives. In that case, would the exploitation of words such as "Secret Formula" and "Homemade" meet the basic requirements from the three-pointer guide? Let's evaluate.

SAFETY
The probability of safety from "secret-homemade-formula" skincare products:
Safe usage of any type of product available is the simplest form of identification when customers select purchases. Even though quality inspection, health inspection requirements of all test items are listed in the cosmetics industry both domestically and internationally as a key criteria, many homemade skincare products do not submit themselves through these processes. Moreover, a lack of the right equipment and the right conditions during the production of skincare products can also widely affect how safe these skincare products are.
You could purchase a skincare product with a secret recipe that proves to have much success with its customers from online sites such as Facebook, WeChat, Tao Bao, et cetera, but there are also many
hidden dangers within such products:
1) What is the date of expiry of such secretive homemade products?
Most exclusive skincare products in the market have a certain shelf-life or a certain guideline to the recommended lifespan of their product. Just like make-up cosmetic products, those that have expired cannot be used- its as simple as not eating mouldy bread.
2) Are these self-made products stored in the right environment?
The wrong environment can very well cause certain ingredients to be reactive or turn bad. For example, plant extracts have to be stored in low temperatures. So how could we be sure certain online sellers have kept the ingredients in the best scenario? Things get worse when you are unable to seek help as there is no validation by any authorities or an actual manufacturing process to count on.