Final answer:
The disadvantages of an architecture that spawns child processes include unintended consequences, increased cost and resource consumption, and potential issues with system cleanliness and manageability.
Step-by-step explanation:
When discussing an architecture that spawns child processes, several disadvantages can emerge. One significant issue is the potential for unintended consequences, as systems are not always predictable when they start to interact dynamically, and spawning processes can lead to unpredictable behaviors. Another disadvantage is the cost implication, as spawning many processes might consume more system resources than anticipated, leading to degraded performance or higher operational costs. Lastly, the topic of cleanliness comes into play; the creation and management of numerous child processes could result in a cluttered and less maintainable system if not managed properly.