What if I can't send funds on Coinbase?

Could you please elaborate on the possible reasons why an individual might encounter difficulties sending funds on Coinbase? Are there any common technical issues or security measures that could potentially hinder the transfer process? Additionally, what steps should a user take if they encounter such a problem? Would it be advisable to contact Coinbase's customer support for assistance, or are there any self-help resources available to troubleshoot the issue? Clarifying these points would greatly assist those facing difficulties in executing transactions on the platform.