Most of the times I use to convert bitcoin to some altcoin like doge or ltc or eth
Really? . What do you think if you need your transaction quickly ? Because swap your bitcoin to altcoin is time consuming and you never know the price may crashed suddenly when you try to convert to altcoin also how long your transaction to get confirmed.Send directly in your wallet and adjust your fee to get quicker confirmation.
, If he needs his BTC quickly, he simply sends it directly without swapping them because it's basically just an option for him to avoid the overwhelming fee in bitcoin blockchain. Within the time intervals needed for a coin to be swapped and be sent to the targetted wallet, there might be a fluctuation happen, but mostly just a small margin, if he's fine with it, it's ok, though.