It's because the OP has a REALLY BAD HABIT of shutting the PS2 in a odd way which leaves the LASER PICKUP close the center of the disc.
The PS2 SLIM MECHACON is programmed to PULL THE LASER OUT when the console is turned off or the lid is open.
The reason for that is to prevent that the FLEXIBLE CABLE which connects the LASER PICKUP to the motherboard is not left in a position that will cause it to be EXCESSIVELY BENT.
The results of the FLEXIBLE CABLE being EXCESSIVELY BENT is that it will touch the surface of the inserted media causing circular scratches.
l_oliveira now supports READING AID
SCPH-10000_GH-001 SCPH-15000_GH-003 SCPH-18000_GH-008 SCPH-30001_GH-005 SCPH-30000_GH-016(V4) SCPH-30001_GH-010(V4)
2xSCPH-10190, 2xSCPH-10350, 2xSCPH-10280
"**** j0 hackers!"
-Sjeep (As seen on TOXIC OS ELF...)