Cloud-based phone systems are no different from any other cloud solution: Their biggest boon is that the shift to the cloud shifts the burden of managing and maintaining a secure, scalable, agile calling system from IT to the service provider, effectively freeing up IT teams to focus on higher-value business goals. When IT teams don't have to worry about maintaining legacy hardware or untangling complex software and can manage the phone system like they would a mobile app, they can devote their time and energy to other priority projects.
While these resource benefits affect the bottom line, the most significant advantage comes from moving from a capital expense model to an operating expense (opex) model: Instead of a heavy one-time investment in an on-premises phone system that'll one day be outdated, the pricing model for cloud-based phone systems is based on a predictable, monthly per-user subscription basis.
From a functionality standpoint, a cloud-based system often provides the agility and mobility that most legacy systems can't. If you're in the customer success or sales departments or even the C-suite, missing a client call isn't an option. Your system needs to connect to whatever device you're on, wherever you are, whenever someone's calling you. Most cloud-based solutions allow multiple devices to ring simultaneously.
Cloud-based solutions are scalable, too. As remote work becomes the new normal, employees must be able to access their calling services via their laptop, mobile devices or tablets. The mobility and scalability that a cloud solution provides are also valuable to businesses affected by seasonal spikes in call volume.