About Sliding Door Locks
It is always important to know the state of your sliding door lock and make sure that it is latching securely by trying to forcefully shake the door back and forth and see if it breaks open. Many times if the latch and keeper are not properly aligned the locked door could easily be forced open just by shaking or pulling it aggressively. If this is the case, an experienced locksmith should know how to align the parts properly.
If you are looking to make your sliding door more secure you can always install a security bar or install a motion activated outdoor light above it. An alarm can also be a good deterrent as long as you let the burglar know it’s there by warning him with a visible sticker.