Our bodies are made of chemicals, so is our skin. Plant extracts and DIY kitchen cabinet masks are made of complex chemical compounds, too.
In fact, their chemical composition is more complex than the man-made skincare ingredients. In other words, with a lab-produced ingredient, you are getting one pure well-known substance.
Plant extracts, on the other hand, can contain hundreds of different chemicals, with complex interactions between them.
Some of these chemicals and interactions are great for our skin, but some can be unpredictable and even harmful (some of most deadly poisons are of plant origin, after all)
The complexity of plant extracts also means that their exact composition varies depending on hundreds of factors, including exact plant species, origin, soil, wind, humidity, shade, sun, insects, time and method of harvesting, storage and extraction. It's often impossible to know for sure how much of an active compound is present in each batch of an extract, so its harder to tell, on one side, if you are getting enough of the substance from your product to see a benefit, or, on the side, if it's getting too much for your skin to handle and can cause problems.
Plus, lab-produced ingredients could also often be more sustainable than their plant-derived alternatives - typically a small unit of a plant extract or an essential oil made of a few kilograms of the raw plants. It requires agricultural land (and a lot of it - especially if cultivated organically). Because of all these reasons, at What's In My Jar, we've decided not to discriminate between plant and synthetic origin of skincare ingredients - we love both plants and lab creations, as long as they are safe and good to the skin!