Jeez, PATA is not hot plugging capable (without extra hardware)! You had just luck with the 5 times.

"The current standard-based design of the PATA device connector is not capable of supporting hot-plug since its pin lengths are not staggered (Figure 3). This means that when an HDD is inserted into the host system slot, it will simultaneously connect power, ground and data signal contacts. This does not provide a "controlled" connection between the host system and HDD, and may damage the HDD."