You are right, of course it's not 100% deductible. I am not advocating spending wildly on things you don't need for the business. If you have lots of revenue and not a lot of expenses, it makes sense to splurge on physical assets you can use and then expense and in the future sell. I.E. computers, networking equipment, storage, monitors, etc. Furthermore, it also make sense to spend on things that can help you grow the business like advertising, marketing, office space, employees. Again, better to spend and get the tax deduction, and have the resources that grow the business.