Why might the largest tsunami in modern times have only two recorded deaths?

1- tsunami warnings can now go through on phones and television, long before it happens to give people chance to escape
2- more countries can afford better tsunami-proof buildings which can withstand a tsunami
3- air travel is far more developed and can afford to get large amounts of idols out of the country quicker
4- people have been trained in what to do if a tsunami occurs and are prepared

Its decreasing because of illnesses