Why keep a car when check engine light is on for a 2nd time at 1100 miles?

What is your question?

1st time: The dealership switched the oil supply valve(osv) to see which one is malfunctioning. Bring it back when check engine light goes back on (mileage 600 miles) 2nd time: Check engine light went back on. Dealership says they will have to replace the cam gear shaft.(Mileage 1100 miles) Do I have a lemon? Help!