As use of bitcoin is scheduled to grow, the pace of the production of bitcoins needed to support the market does not keep up.
This results in a steady increase of the value of bitcoin, which is good for adoption (more people will buy it to speculate and sellers will accept it), but endangers it as a mean of paiement as buyers are always better of paying in $, which devaluates over time, instead of Btc, which will increase over time.
The reason bitcoin will not be used for daily exchanges is the same as we do not use gold anymore. But since Btc has no intrisic value, I hardly see it as a reserve money.