If you are talking about transistors, when they were invented the only other alternatives were triodes (vacuum tubes) or mechanical relays. Both were orders of

If you are talking about transistors, when they were invented the only other alternatives were triodes (vacuum tubes) or mechanical relays. Both were orders of magnitude less reliable and slower in terms of switching speed. When transistors were invented it was a mad dash to get them cheap and small enough to replace everything else, because everyone could tell they were the future. It took 9 years between the first transistor and receiving the Nobel Prize for it.