This type of boot tends to be very popular.
It offers a player the opportunity to adjust their footwear depending on the conditions.
If the pitch is particularly muddy then it is a good idea to use a longer set of studs, changing to shorter studs on a drier day.
And an extra set of studs can be purchased far cheaper than another pair of boots.
When changing or tightening studs it is a good idea to apply a bit grease to the thread to prevent rusting.