People cannot spend what they don't have. So I think the initial stage for bitcoin adoption is to buy bitcoin and own it first, and even multiply it within a long time frame so that when these people have decided to spend their bitcoin or use them as a payment tool, they will have sufficient amount of bitcoin to spend.
However, since the current status of bitcoin is more of a store of value that increases its price whenever the market is bullish, we can't expect from the people to spend it but rather accumulate more bitcoin to multiply their future profits.
Bitcoin adoption can wait, people will eventually use bitcoin as a currency, but maybe it will be highly possible when bitcoin price itself becomes less volatile. For now, high volatility means bigger chances for long-term profitability.
For Bitcoin to be widely used as a currency, it doesn't just need to become more stable. More importantly, it needs government approval.
If governments don't recognize Bitcoin as legal currency and allow people to use it, idea of using Bitcoin as a common currency will be difficult to turn into reality, no matter how much the network grows.
To me, governments are one of the biggest barrier because it's hard to see them willingly accepting a currency they don't control becoming widely used.
