When does lock conflict occur?

Lock conflict occurs when two or more transactions attempt to acquire locks on the same resource, such as a database row or table, but are unable to proceed because they hold incompatible locks. For example, if one transaction holds a write lock on a resource while another transaction tries to acquire a write lock or a read lock on the same resource, they will conflict, leading to potential blocking or deadlock situations. This conflict can hinder the overall performance and throughput of a database system.