When approving payment for contractors' invoices, you should typically be able to approve multiple invoices at the same time and make one payment.
The only exception is when Stripe Connect as well as Bank accounts, are chosen as withdrawal methods by contractors on their invoices. For example, a client is trying to approve three invoices from three different contractors. Contractor A has Stripe Connect as a withdrawal method and Contractor B & C have their bank accounts as withdrawal methods. The client cannot "select all" and make one payment. Instead, the client will need to select the invoices with similar withdrawal methods and then make payment for them.