This is because a mango has only one seed and can be found at the center of the fuit. When held by a hand, one may find that it has a compressed weight and is comparable to the weight of other fruits such as an orange or an apple. However, because of its compressed weight, one may be careful of dropping the fruit because it can cause damage to the fruit's inner flesh that can similarly damage its juice's taste. Based from my experience, a mango that has been dropped for some hours ago does not anymore taste as sweet as it should be. Instead, some unlikable acidic taste is formed which tastes almost similar as an over-riped mango.

While peeling the skin of a mango, one may find that it is slippery to the hand. This is perhaps because of the sugary and acidic flavor of the fruit. But, the juice of both the ripe and unripe mango is splendid. Ripe mangoes are sweet...

In fact, there are different kinds of food in which mango is being used as a flavoring. Unripe mangoes also taste good especially if one is fond of sour-like tastes. With a combination of salty or sweet flavor, the acidic taste of an unripe mango can tolerate the saliva that the acid of the unripe fruit produces in a person's mouth.
With all the good and tempting characteristics of a mango that you have read in this paper, I wish to give you one piece of advice though. Because of the compressed weight of a mango fruit, dropping it may cause you with bruise especially if it hits your foot. This is just a cautious reminder to people who have never tried to eat mango.

Reference

Mango. http://www.crfg.org/pubs/ff/mango.html