One of the great things about the old steel framed bikes is they were made by hand. A framebuilder put a handful of tubes into a jig, brazed them together, and then filed the joints to clean them up. A lot of the great names in bike building were literally a few people working in a small shop, making a few hundred frames a year.

Steel frames can often be repaired and if necessary, a damaged tube can be replaced with a new one. Minor dents can be filled with brazing and a twisted frame can be realigned. A carbon fiber frame will only bend so far and then it breaks. A steel frame can last forever as long as it's kept dry. The adhesives that hold a carbon fiber frame together can break down over time.

carbon mtb rim

carbon mountain bike rim

carbon road bike rim