dear practo user your expectations for erections within 30sec are incorrect .....usually you need to have proper spontaneous sexual intimacy with your partner and the type of atmosphere (quality of mutual behaviour of partners is directly proportuinal to this problem) also their ate many other factors psychological high frequent masturbation overindulgence in sexual activities mental stress physical stress and many more porn clips watching for long period possible that  because chronic masturbation you are not getting enjoyment which results into incomplete erections