There many types of traders in the forex, but we can simply classify them into three groups which would include day traders, position traders and then swing traders. Though some forex traders may see a position's trade or buy-and-hold strategy as an investment, in practical terms, it is just a long term trade. In the forex, if you want to buy and hold a currency pair, I would prefer you sell a currency that pays a low interest rate, the yen is an example of such and then proceed to buy a currency that pays a high interest rate, such as the AUD which is the Australian dollar. Yet this is a carry trade, where you will make money from the interest differential between the two yen and the Australian dollar.
One use of buy and hold that I must condemn is when a forex trader hold onto losing trades,expecting them to reverse and come up to profitable direction in the long run. Although you can say this is pretty logical; if a trade is losing, you will then hold onto it till it around and becomes profitable. But it doesn't work this way in the forex market because if the currency market had worked like this, we will all be in riches because no one will lose at all in the forex.