Cloud storage services usually start you on a free basic plan. That plan gives a limited amount of space, such as 5 GB, and a limited set of features. When you need more room, you pay for extra capacity, normally as a subscription that renews regularly.
Scalability means you can increase or decrease your storage easily as your needs change. If your needs grow, you move to a bigger plan. If they shrink, you drop back down. For example, a community radio station might keep 4 GB of interview recordings on the free plan, upgrade to 200 GB while editing a documentary series, then drop back to the free plan once the series has aired.
Scalability keeps costs under control. You only pay for the storage you actually use, so you do not buy a large hard drive that sits empty for most of the year. Paying a small subscription during busy months and nothing during quiet months is cost effective, and being able to step back down matters as much as being able to step up when you only need extra space for a short time.
Cloud storage is not usually offered with unlimited space. Even paid plans have a maximum capacity, so "unlimited storage" is not a standard benefit to claim.
Pearson BTEC Digital Information Technology · Features of cloud storage
Pearson BTEC Digital Information Technology · Features of cloud computing