When I sit down to formulate a new cleanser, whether it's a liquid wash, a solid bar, or anything in between, there's almost always one surfactant I reach for first to kind of anchor the formula around, and then I build from there. I'm curious whether you have a default starting point too, or whether you approach each formula differently depending on what the product needs to do. My own starting point has actually changed over the years as I've worked with more surfactant types, which is part of why I find this question interesting to ask. It doesn't matter whether you're at the early stages of learning surfactant systems or you've been working with them for a while. Any answer is genuinely useful here. What's the first surfactant you reach for when building a cleanser, and what made it your go-to?

Quick one this week: I want to know where people actually are with stability testing. Which of these best describes your current process? Pick what applies. Multiple answers are fine if you do more than one. And if your process is something different entirely, tell me in the comments. I'm not looking for ideal answers here, just an honest picture of where people actually are, so I can see how I can help.