This warning has been repeated over and over again, and thankfully most western tourists heed it. Three individuals were executed last week for drug offences which brings the total to 17 this year. A death sentence is automatic if you bring in more than 15g of diamorphine, 30g of cocaine, 250g of methamphetamine and 500g of cannabis. With cannabis still on sale in Bangkok, don't even think of trying to hide any in your luggage if Singapore is your next stop.

https://www.bbc.com/news/articles/c8dymv623q0o

I've seen some news reports in The Straits Times of people going into Singapore from Thailand with cannabis in their luggage and they all pretty much said the same dumb thing "oh sorry I forgot I had it but I bought it legally in Thailand", I guess that's the defence by ignorance attempt. Of course the Singapore authorities couldn't care less if it was purchased elsewhere legally or not and that excuse just didn't work. Maybe they should have taken a few minutes to double check their luggage before leaving Thailand.