The identification of performance obligations is a critical aspect of revenue recognition under IFRS 15, and it's importance can be noted due to the following reasons:

1. Basis of Revenue Recognition: Performance obligations form the basis of revenue recognition under IFRS 15. Revenue is recognized when (or as) a performance obligation is satisfied by transferring a promised good or service to a customer.
2. Accuracy of Revenue Recognition: The accuracy of revenue recognition depends on correctly identifying the performance obligations in a contract. Failure to identify all performance obligations can lead to over-recognition or under-recognition of revenue.
3. Timing of Revenue Recognition: The timing of revenue recognition depends on whether a performance obligation is satisfied over time or at a point in time. Identifying the performance obligations correctly can help determine this timing.
4. Allocation of Transaction Price: The transaction price in a contract is allocated to the identified performance obligations in the contract. If performance obligations are not correctly identified, this can lead to an incorrect allocation of the transaction price.
5. Assessing Changes in Contract: Any modifications to a contract are assessed based on the performance obligations in the contract. Thus, proper identification of performance obligations is necessary for assessing the impact of any contract modifications.
6. Disclosure Requirements: IFRS 15 has specific disclosure requirements based on performance obligations. Entities are required to disclose information about their performance obligations in contracts with customers, including a description of the performance obligations, the transaction price allocated to the remaining performance obligations, and an explanation of when the entity expects to recognize revenue for those performance obligations.

Therefore, identifying performance obligations is a crucial step in applying the revenue recognition model of IFRS 15, and it directly affects the amount and timing of revenue recognition.