How do I choose between electronic lock, mechanical lock and IoT?

Use a mechanical lock where there is no power budget, no IT support, and no need for data — it is the most robust and lowest-cost option. Use an electronic lock where users expect a premium experience, and you want card-based or PIN access without a network. Use the IoT lock when you need central control, remote authorisation, usage statistics, or time-based billing. Many projects mix the three lines across different zones of the same building.