...and you may get into life threating situation.
I came across this interesting article, stating that even officially approved landing procedures may be flawed. Things happen, but it makes me wonder how many procedures are flawed (potential safety hazard).
"The weather at Saratoga Springs, N.Y. on the night of July 13, 2008 was 1,100 overcast, one-and-a-half miles visibility with moderate rain, and wind calm. Albany approach control vectored us for a GPS approach to Runway 5. We intercepted the inbound course toward the airport. On our descent, all altitudes and altimeters coincided with the information on the approach plate. Before reaching minimums, my co-captain called, “Runway in sight, twelve o’clock.” I responded, “Going visual.” Looking up, I saw the runway was dead on at 12 o’clock. Before going visual, all indications on the flight director were centered and exactly where I wanted them. My co-captain called, “Ref plus thirteen,” then immediately called, “Trees! Pull up, pull up.” I simultaneously went to max power and rotated to a 15-degree deck angle. The aircraft hit a pine tree and, we learned later, cut eight feet off its top. I still had the runway in sight, and after making a quick scan of the panel I replied, “We have good gear indication, and pressure is up; I plan on landing.” My co-captain replied, “I concur.”