Outcome and output are very different.
The output is, for example, the app, the feature, tasks, and activities you are doing now.
The outcome is the result of that work. It's a defined, observable change you desire to achieve supported by a specific measure. You need to balance and achieve both customer and business outcomes.
The customer outcome is the value you want to deliver to the customer and the impact it will have on their life by launching that app, feature, etc.
The business outcome is the impact you want to drive for the business, based on the current vision and strategy, by launching that app, feature, process, etc.
Everything you do is additive, so knowing the difference and establishing the customer and business outcomes first will help you determine if what you are working on (the outputs) is moving you closer to achieving those desired outcomes. If it's not, you have the flexibility to iterate, experiment, learn, gain evidence, and track to find the fastest path that will.