DAMNED LADDERS !
If we believe the “Commentarios…” of Braz de Albuquerque, son of the great Albuquerque, on the 26th March 1513, Afonso de Albuquerque failed to capture Aden because the ladders he used to climb the walls of the city were too short and too fragile also. They broke under the weight of the heavily armed Portuguese soldiers.
If we believed the XIX century copyist of the Syair Perang Johor (a poem about the wars fought by Johor), on 14th January 1641, the Dutch failed to enter Melaka. They walk by night to the bottom of the walls (St Dominic Bastion). At dawn they throw their ladders against the wall. Shame to Hollanders! They realise the ladders were two and half meters too short to reach the top of the wall, leaving the Dutch Captain agape. Fortunately, the Johor warriors save the day. They attacked from South (Ayer Leleh) and they stormed the fortress, killing many Franks and the Dutch claimed victory.
If you believe me, on 19th March 2018, as my ladder was too short to reach the roof of my house to replace a broken tile, I put it on an old wooden bench. The bench broke, I fell and I ended at the hospital with a broken wrist.
Now, you know why it is bad luck to walk under a leaning ladder.