As with most things I DIY I do it for two main reasons: to reduce toxins in my home AND to save money. I started hunting for a DIY dishwasher detergent recipe several years ago, and starting making my own about 2 years ago. After reading through many recipes, I came across one that primarily uses lemons. WHOLE lemons. That might not seem very exciting to you BUT I have a lemon tree that overproduces lemons so this recipe was a perfect fit. Although I do use my lemons in cooking and to make lemon juice (even freezing it into lemon ice cubes) I STILL have an overabundance (there’s only so much you can freeze, drink, and cook with), so this dishwasher detergent recipe is a great way to use them while making a useful product.
Edit: You can make this DIY with limes too and it is so much easier because limes have little to no seeds. I discovered this by chance when I received a bunch of limes for free. If you are able to acquire limes instead of lemons, DO IT!