they keep on testing, and thereby waste valuable taxpayers' money which could otherwise have been put to some good use, on an already tested and somewhat established technology - chinese to be precise...
The country is downrightly following a flawed strategy (and we know who is behind developing it).. its trying very hard (and quite futile to be honest) to be seen as the major player in the region by dint of these military displays/exercises/extravagant-spending on useless stuff etc... but lets be honest, as long as the country doesn't achieve economic and technological excellence over other players in the region, it would continue to be seen as the underdog by the rest of the world...
other countries in the international community neither get impressed by these 'pyrotechnic' displays that pakistan put up every once in a while, nor are they given much of a coverage in the international media.. so yea, the whole exercise just goes to waste... better luck for the next fireworks show..