It's hard to expand in the industry these days as there are a lot of web hosts and the big companies being bought out by EIG. However you can grow by offering something your customers need…
- Security; a lot of customers put security first they don't want to hear that their information has been leaked online or that their card details have been stollen and used for fraud. If security isn't important to you then you loose that client.
- Reliability; customers like a reliable provider who is there when they need them and provides good and helpful support.
- Transparency; some customers prefer their provider to be transparent when there are downtime, if you don't inform your customers why the service is not available and / or you don't keep them updated they will leave. That's more important than good up-time.
- Price; you can get new customers if you have discounts too as stated above, even if it's the first month only, it will allow clients to test out your support and service before paying and committing to your business.
- Freebies; some customers like the odd freebie(s) like a billing system for resellers, ssl for both web hosting / resellers, free domain if you purchase yearly.
That's what helps most business expand, and the more happy customers you get the more new customers you will gain by word of mouth and reviews.