When you spend money on an item in the business that is an expense of the business (like your monthly rent or advertising, etc.) then you'll typically be able to deduct all of that type of expenditure immediately. If the capital you invest in your business is for an asset (like a franchise fee or an equipment purchase, etc.) then you will typically deduct this expenditure over time by either depreciating or amortizing the asset value.
The difference in how you classify an expenditure (and therefore on what terms you are able to deduct it) can make a big difference in how much and when you owe in taxes. This is why consulting with an expert on these types of decisions is well advised.