The characters were running out of resources the longer the show ran, and Galactica was already so old that she was on the verge of being decommissioned anyway.
The improbable victories ultimately felt all the sweeter for how the fleeing humans cobbled together solutions mostly out of courage, creativity, and spare parts.
That said, the fact that Galactica wasn’t a gleaming starship that could engage in constant grand space battles or survive endless explosions might have played in the show’s favor.
We were following the stories of refugees fleeing Cylons who wanted nothing more than to finish the destruction of the human race that they started when they destroyed the Twelve Colonies.