Bitcoin is purely speculative market right now. Bitcoin is supposed to be a currency - thing you pay with. Right now constant deflation means nobody uses it to pay, which defeats its purpose.
Bitcoin is also not gold. It has no inherent value, it's not useful in any way besides as payment instrument and right now utility of BTC as payment instrument is close to zero.
Finally, Bitcoin is extremely expensive to maintain (electricity and computing power) and there is no way to lower that cost. Once BTC network processing power is too small percentage of world's total processing power, it becomes feasible to perform an attack on a Network (you need 51% as everybody knows).
So, given that production of Bitcoin has a hard limit, at some point increase in price won't be able to offset resources necessary to mine, which will cause collapse of network processing power, which in turn will make network susceptible for attack.
Mind you, it has nothing to do with product competitiveness(contracts, transaction times etc.). Bitcoin is designed in a way that is not sustainable and it will become clear at some point.