> Land taxes are efficient. They are difficult to dodge; you cannot stuff land into a bank-vault in Luxembourg. Whereas a high tax on property can discourage investment, a high tax on land creates an incentive to develop unused sites. Land-value taxes can also help cater for newcomers. New infrastructure raises the value of nearby land, automatically feeding through into revenues—which helps to pay for the improvemen…
The harm for the owner in leaving the lot vacant for a decade is opportunity cost. If he is in a valuable spot , it would be advantageous to sell and just do something else with the money. Imagine high land taxes in the middle of the desert. Is it an incentive to build? Quite the contrary.
So, if he believes that the value of a certain area will increase by 50-100% over the next decade, and he can borrow against it for cheap, it actually wouldn't be advantageous to sell it.
If land taxes would be higher, he would probably sell it.