Sometimes a direct question like this requires an answer in a form of a similar question to reveal the essence of what could really be going on. Consider these two substituted questions:
1) "Why should I remain focused on my fiance when there are other people offering me allegedly similar marriage opportunities?"
2) "Why should I focus on picking up this $100 bill when there are other people offering me allegedly similar (counterfeit) $100 bills?"
Maybe you may say this is not the same scenario, but commitment is commitment, and nothing else. If you have truly found what you are looking for, nothing will stop you from giving it your full attention. When you make a decision about something important to you, you are saying that you have cut off everything else that can hinder that decision to stop you from moving forward with it.
Your question tells me that you are in the process of making a decision, but you have not arrived yet. When you get beyond your 'why', 'remain focused', 'other companies' and 'allegedly similar opportunities', and you should, you will put on your 'focus' and get to work to build you a big and profitable business.
Sometimes a direct question like this requires an answer in a form of a similar question to reveal the essence of what could really be going on. Consider these two substituted questions:
1) "Why should I remain focused on my fiance when there are other people offering me allegedly similar marriage opportunities?"
2) "Why should I focus on picking up this $100 bill when there are other people offering me allegedly similar (counterfeit) $100 bills?"