For it depends on each individual desire, because I myself sell Bitcoin to buy altcoin.
But I sometimes do the opposite too .
that usually we do in crypto market trading.buy or sell altcoin and bitcoin to get much profit and money.no matter with strategy we do, as long as it can make profit just do it.
Yes its like making your funds more profitable and convenience of it in making money, all funds should be have a better place to be sold , it is usually done here in crypto that you sell alts in order to buy btc or sell btc to buy some profitable alts, it all depends on the price of the market, it should be done with great and careful decisions and have a better mind set in giving yourself a profit.