Is there a reason why there is a need to connect a powerful resistor to the base pin of a transistor, other than the base has a lower maximum current rating?

On circuits bought within some appliances, I see the transistor base pins are connected to a powerful resistor, usually within the 1000s of ohm, and this is enough to make current almost non-existant on a reader... why does the base resistor need to be that powerful?

1_is it to prolong the transistor to its maximum life span?
2_is it that each transistor has a SPECIAL amperage that makes it turn on and off, other than that maximum base current rating?