Hi guys, hope all of you are doing well.
I work in the product management/marketing side of beauty industry but as the brand I work for is not that big of brand yet, I also have some knowledge in the formulation side of it.
Just writing this post to share my knowledge to the beautiful consumers on some of the commonly discussed topics on this sub. I am not gonna reveal the brand as it would be a promotion of it and my goal is to just spread knowledge.

TLDR: Some of the things I have learnt till now working in beauty industry that I thought people on this sub would like to learn about and some of the things you should look out for while making purchasing decisions.

1. Greenwashing: It is 100% absolutely real. But only when the brand’s only point of selling is sustainability. Environmental benefit should be a plus, never the main advantage of a product.
   Look for things that actually solves your problem.
2. Sneaky changes in formulations: Again 100% real. Most of the time, after a product has been out for a long time and the brand already has a customer base, they’ll change the formulation because they want to: Cut down on manufacturing cost, a new change in policies imposed by FDA, Health Canada or EU & UK Health Regulations, test different textures and the response towards it (rare but it does happen and if the response isn’t good, they go back to the old formula).
3. Luxury vs. Masstige vs. Drugstore Brands: A hero is what works for YOU, not the brand. But why the difference in the prices with the EXACT SAME INGREDIENTS? You’d think it’s the brand name you are paying for which is true 20% of the time but it’s actually the FORMULATIONS you are paying for. Brand One’s product won’t work for you but Brand Two’s product containing same ingredients might work for you because of the way it was created. Concentrations, R&D, quality of ingredients, ethical sourcing etc. etc. This doesn’t mean at all that drug store brands are bad or luxury brands are ripping you off (most of the times, Apparel Industry is actually where luxury brands tend to rip off generally).
4. Should you use expired beauty & skincare products?: Generally Makeup products older than 18 Months shouldn’t be used however it’s still okay to use them for up to 3 years (If they remained sealed for a long time after you got them). Mascaras older than 3-4 months shouldn’t be used. Lipsticks Can stay AMAZING up to even 24 months because lipsticks don’t hold much bacteria (unless you share it with someone on a regular basis).
   Expired Skincare SHOULD NOT EVER be used. It can cause some really bad skin irritations and breakouts that could take months or even years to treat. Please be cautious of it. Generally, shelf life of skincare product tends to be of 24 months which is more than enough.
5. Selling same product under different name: Yes, It happens. A LOT. Usually when brands reach a certain point and their R&D is not going on schedule or the way they thought it would go, they make a little change in either shade or some formulation or concertation of ingredients and market it as a different product. Doesn’t necessarily mean it’s bad but strictly in my opinion feels a little deceptive because people are investing their hard earned money and their valuable time in your brand, make it worth it.

These are some of the major things I have learnt. If you have a different question, please feel free to ask and I’ll try to answer it to the best of my knowledge.
Also I could definitely tell you guys all the price structure and the strategies that brands implement and how prices are decided but it’s already a long post and I don’t wanna bore you guys.
Thank you for reading, if you guys like it, I’ll be open to sharing more things from the business side of beauty.
Stay safe everyone.