Cages for MRT stations

The recent tragic case of a promising Thai student falling into the MRT track and losing both her legs must have made many people thinking. How to prevent such accidents from happening in an area that apparently is having an unusual number of such accidents. They are preventable of course, or could be greatly reduced. The artistically attractive and high tech barriers that have been erected in some stations seem to be the solution to such problems. They are expensive and require high technical and engineering skills to instal them, and the poor commuters will eventually have to pay for them. The costs could come in tens or hundreds of millions if maintenance and service and replacement are included. Funny thing is that many must have seen railways running through the centre of a market, or people living a few feet from operational railway lines and nothing of such happens to the residents. Is it a miracle, that there is an invisible hand preventing accidents from happening in such a dangerous situation? There are many kinds of people who will end up in the tracks, intentionally, by mischief or by accident. There are the suicide squad that comes with one purpose, to jump when the train is approaching. There are the real suicide bombers that will blow themselves up and the trains in the same time. Then the mischievious kids and their pranks, and the normal accidents like the school girl, falling for some unexpected reasons. The high tech barriers cannot do the job properly against people who are bent on jumping on the tracks, even with CCTV cameras. You would need to put all the commuters into a cage if absolute safety is needed. Also, the expensive high tech system is superfluous, overkilled, and a big waste of money. It is like, since the commuters are crying for safety, give it to them at whatever cost, and make them happy, and make them pay. To prevent simple accidents like people falling into the tracks without intending so, a simpler barrier could do the job just as effective as the high tech barrier. A railing like those in high rise flats, maybe double layer of railings could do the job just as fine. Low cost, easy to instal and minimal maintenance. What is it so difficult to put up simple railings, couple with a few measures of a pair of watchful eyes through CCTVs, alert staff and alert drivers?