Final answer:
The use of steel frames in the early 1900s was initially limited due to poor knowledge of iron's properties and the high cost of steel production. However, advancements in steel manufacturing made steel more affordable and readily available, leading to increased use in architecture.
Step-by-step explanation:
The use of steel frames was initially limited in the early 1900s due to a few factors. One limitation was the poor knowledge of iron's properties as a construction material, which led to the collapse of early mills. It was not until the early 1830s that the section beam was introduced, leading to widespread use of iron construction. Another limitation was the cost of steel production, as it required significant investment. However, advancements in steel manufacturing processes, such as the Bessemer process and the open-hearth process, made steel more affordable and readily available, resulting in its increased use in architecture.