Hi Sain Cai,
Free hosting is an ever-changing industry. New companies enter and exit at an incredible rate. There is always a steady stream of dissatisfied clients who will head your way from the competition. The trick is, can you keep them all happy?
You can't. I managed to do it for the first 1000 clients, answering with a 100% satisfaction rate, but after that, trouble began. Too many accounts, server lagging, and support requests. The larger you get, the larger the part of your job will be crisis management.
And absolutely do not do this if you are looking for income. Wrong industry...
I also want to mention, if you want an edge on the competition, build your own software. It might take a while, but here I am able to upgrade absolutely any feature for a client literally in the middle of a chat conversation (3 seconds), while the competition has to spend about a minute fumbling through the links of their 'Modify An Account', then select the account after it loads, then focussing on the textbox, typing it in, and finally it's done. (I hear it's even worse for the other panels.)
This is true for any industry - clients want to talk to people, and support is one of the most important jobs you can do. Always make sure you have addressed what the client has asked, or given a date/criteria when it will be done. And close your messages asking if they need anything else. The best support system avoids the use of numbers. Clients are people, not numbers. Well, that's how I run things anyways, and my clients all agree with it.