Why can't I hold all these wizard towers

Ardmore Round Tower

Summon Wizard Tower
Magic User, Level 1
Duration: Until sunrise
Range: 500’ on ground under open sky

A wizard tower that has been placed under the “Bind Wizard Tower To Summoning” enchantment (which one exactly depending on the vagaries of cosmological fate) erupts from the ground 500’ away from the caster. At the next dawn, sunlight causes the tower and anything summoned with it to dissolve, returning whence it came. If someone who enters the tower writes up a session report describing their explorations, tribulations, and likely death and shares it with the OSR community and/or creator of the tower, they receive XP equal to 500 multiplied by the (lowest) character level intended for the tower.

Bind Wizard Tower To Summoning
Magic User, Level 5
Duration: Permanent
Range: Touch

The creator of a wizard tower writes it up as an adventure module and shares it with the OSR community. The tower then becomes summonable by the Summon Wizard Tower spell. Details of session reports from explorers of the tower via the Summon Wizard Tower spell may alter or add treasure or magic items to the tower in the creator’s world, and subsequent summonings.

Some pre-bound Wizard Towers ripe for the Summoning: