Final answer:
Short-term memory cannot hold unlimited amounts of information due to memory trace decay and proactive interference, as opposed to the virtually unlimited capacity of long-term memory.
Step-by-step explanation:
A disadvantage of short-term memory is that it cannot hold unlimited amounts of information. Short-term memory (STM) has a limited capacity, typically holding about seven bits of information before it is either forgotten or stored into long-term memory. One of the issues with STM is that over time, memory trace decay occurs where the memory trace becomes less activated and the information is forgotten. Additionally, proactive interference can pose a problem as previously learned information interferes with the ability to learn new information. Unlike short-term memory, long-term memory does not face these constraints, as its storage capacity is believed to be virtually unlimited and encompasses information beyond just a few minutes ago.