profitability is a business's ability to generate earnings compared to its costs over a certain period of time. this is possibly the most important aspect of any business idea in the long term, as this is what makes a business survive in order to keep having the impact that it has. profitable ideas need a strong revenue stream against its costs and this tends to create the success of the business, however some companies defy this and make losses to begin with, yet are still exceptional business ideas that are worth billions.