I know all the rage currently is to discuss both communication/giving channels and engagement as key
If donor retention is a desired outcome for you it begins with your organizational structure and culture , characteristics of your staff and the environment that is created for them to perform within. Retention is not an outcome as a result of doing X to another person. There are a couple of accounting phrases worth a closer look: FIFO and LIFO are keys to what creates extraordinary increases in both donor satisfaction, their sense of connection and ultimately their decision whether to stay longer. Retention is a direct result of the environment that is created for the workforce responsible for delivering the donor experience. What goes in is what comes out.
If you want to begin to understand what steps that you need to take in order to increase the lifetime value of a donor to your organization start with walking out of your office door. What is the environment with the staff and how is their energy? is there laughter? are people talking about getting together after work? is there any highly engaged group having a conversation about creating something extraordinary for their customers?
Suggesting that engagement is the focus of generating retention is the equivalent of suggesting you need plates in order to have a great restaurant. Of course you need engagement, just like you need plates. However, if there isn't a spirit of creativity, sense of pride and commitment to an extraordinary dining experience in the kitchen and with the wait staff that dining experience will not create a desire for the customer to return.
Start devouring information on creating extraordinary teams and begin the process of understand the unique talents of each person that works in your fundraising operation. Dorothy put it best in the final scene when leaving the city of Oz. It really starts with understanding your own backyard and developing an appreciation for the unique talents of your team. These are the first gifts you need to cultivate in order for others to decide doing the same.