If some of your customers are reluctant to pay by Direct Debit even after explaining the benefits to them, and offering an incentive, you might consider making it compulsory.
This is a good option for your business if any of the following are true:
Cash flow is becoming a problem
You are spending a large amount of your time chasing payments
You don’t have a finance or admin team available to chase late payments
Efficiency of payment collection is important to you
You are looking to grow your business and need to have simple and consistent payment processes that are easy to scale
While you may have to turn down the occasional client who won’t change, you’ll free yourself up to focus on winning the right kind of business.
If you're concerned that making Direct Debit compulsory will drive your existing customers away to competitors, try starting with new customers you acquire first.