Paypal has developed its module so that it creates the temporary order directly in checkout when you click on Paypal. If you then click on another payment method without even having chosen to continue to paypal, the order is still there. Therefore, you can have many "preparing paypal" (Preparing Paypal IPN) in the system.
Preparing Paypal IPN "=" Preparing Paypal IPN ".
In that case, no payment has been made. There can be many reasons e.g. that the customer was denied (no coverage on his card), regretted his purchase or (as we wrote above) chose to pay in another way.
When / if the customer completes a payment with PayPal, the order status changes automatically (may take 20-30 minutes) to "new order". You should also receive an email from PayPal stating that a payment has been received.
But regardless, you should always make regular reconciliations.