Chevrolet: 2001 Chey Cavalier sometimes wont start, chevy cavalier, loose wires

Question
Hi,
I recently purchased a 2001 Chevy Cavalier from friends of the family.  They have never had a problem with the car.  a week after buying the car it wouldn't start.  when i would turn on the car all the indicator lights in the dash would come up and the car would make a humming noise but the engine wouldn't turn.  After a couple of unsuccessful tries i was able to jump start the car and went to get a new battery.  I was told that the battery wire was lose and that was my problem.  despite that i had a diagnostic ran on the electrical system which came up fine and then had a new battery installed.  tonight when i went to turn on the car, it did the same thing again.  after turning the key 4 or 5 times i was able to get it to start but this is getting annoying.  could it possibly be the wire again (the guy told me that he made it as tight as possible).  i had some break work done on the car (they changed out the fluid which is on the other side from the battery) and was wondering if that could have caused something to go wrong.  any help would be appreciated.  thanks.

Answer
Hi Beth;
       I would check for a short ,and any loose wires or un-pluged wires- also does the car have a alarm system , the key switch for it might need a new battery.
       I do not think that the brake fluid did anything at all to cause it.