It might be hot to have quickies, but it does not mean that you do not ever need a foreplay. Some studies even claim that women are waiting for the foreplay more than the actual intercourse. This is warming you up emotionally and sexually, as well, and this is while men are paying as much attention to women as they need.
Also, this is the period that the vagina needs to tent, or to give more room inside it. If we do not give enough time for that, then neither the man nor the woman will feel comfortable at the beginning of sex, or even later on.
But it is not only time for women's sake. Men also need it to get and maintain erection, and if they find it difficult to reach an orgasm, then foreplay is the solution to them, as well. If you plan ahead and you think your relationship is long-lasting – or at least more than just a one-night-stand – then foreplay is even more crucial. It creates emotional stability and strengthens connection between partners.
Obviously it does not only mean that you can give each other massages or oral sex. You can also play something – like strip poker – together, take a shower, or talk dirty, or do anything that turns you on. If it is watching porn, or feeding each other, it does not matter as long as it turns both of you on.