Etcd plays a critical role in Kubernetes clusters by storing and managing the ever-changing state of objects within them. As clusters grow, etcd's storage space can become limited, leading to performance issues if not managed properly. To avoid outgrowing etcd's storage, it is recommended to provision sufficient resources for each node, manage data size, split data across multiple clusters, and allocate enough memory and monitor its utilization. Ensuring low-latency storage, providing sufficient network throughput, and allocating enough memory are also crucial for maintaining a healthy cluster. Additionally, managing the size of etcd's data store through compaction, defragmentation, clearing event objects, optimizing pod specs, and provisioning more than 8 GiB can help prevent performance issues. Deploying multiple etcd clusters can further mitigate risks associated with high event activity in the cluster. By proactively maintaining etcd and leveraging its built-in management functions, Kubernetes users can continue to grow their clusters without breaching etcd's data storage limits.