Tetronious

Ive noticed in the last couple weeks my car has been getting harder to start lately. Like when I go to turn it over it makes this faint clicking sound. I checked my battery with a tester and it says its good. I thought maybe it was the starter. So I took it off and took it to a local parts store and got them to test it. Found out it was bad, so I went ahead and ordered another one to replace it. What I dont understand is the car is only 5 years old and has less than 70,000 miles on it. I would have thought the factory starter would at least lasted to 100,000+. Ive done a compression test periodically on the car every few months for peace of mind since its boosted. The last time I did one I noticed after I did it the starter acted up after that. Could it possibly be that cranking on the motor during compression test could send the starter to its death? Just curious comments or suggestions would be appreciated.

Tetronious

2000 SI
Boosted