BTCitcoin can fall or rise but it can never be stable.
According to market more probability of bitcoin is to fall and settle down which is better for a long term asset.
We can also consider that Bitcoin can do "sideways", we already experience this especially on a few days/weeks, like Bitcoin staying on a particular level, no huge increase or decrease in price.
But as we all know, Bitcoin is volatile. So can rise or fall anytime too with a huge percentage sometimes compare to other assets especially non-crypto assets.
Another thing that Bitcoin for me will rise for the long term is the limited supply of Bitcoin that will exist in the world, basic economics.