Is it correct to incorporate Pending status in tool for Incident Management?

Why do a customer need to agree on marking a incident into ‘Pending state’ and effectively put SLA clock on hold. Incident management tell to quickly resolve/provide workaround to the degraded service. It has become organisation culture to put a ticket on hold when you need other team to respond or when change or problem is invoked. When Customer has agreed a certain SLA then why do we not stick to the SLA and inturn are using pending state as trick to get more time without missing SLA.