With an online business, you can do just about whatever you want with it. The sky is the limit for what you can accomplish online. There are no limits. There is nothing stopping you from taking on multiple opportunities all at once. This way if one opportunity is struggling, you have several others to rely on for income.
The great thing about the internet is that it never sleeps. You can control your destiny based on the amount of time and effort you invest into it. There is nothing stopping you from working 60 or 70 hour weeks to put yourself ahead of the competition. If you desire success and are willing to do anything to reach your goals, the opportunity is there to do just that.