When you start a new settlement, the first asset you click on is 'rushed' and you get it completed next turn. For example, if you select 'shipyard' you will have it ready next turn. If you accidentally click on the wrong item, then cancel it and select 'shipyard,' then nothing is 'rushed' and your shipyard will take about 25 turns to complete. This is a high price to pay for momentarily clicking on the wrong thing.
While you are still in the planetary build screen, whatever you ultimately first select should be rushed. Don't punish users for momentarily miss-clicking.