I personally keep different forms of bitcoin.

Some of my bitcoin I use for trading, dabbling in other cryptocurrencies (what lead me to Steemit).

Some of my bitcoin is used as a savings/investment, held very longterm and not spent on frivolous items.

Some of my bitcoin is used as a currency. Pretty self explanatory.

So there isn't one answer to this post. Use bitcoin for multiple different things and decide the percentage of allocation by your own needs.