Why did Alexander Graham Bell say When one door closes another door opens but you often look so long and so regretfully upon the closed door that you do not see the ones which open for us?

This quote by Alexander Graham Bell serves as a reminder not to dwell on missed opportunities or failures because new ones may be waiting to be discovered. By focusing too much on the past, one may neglect the chances and possibilities that the present offers. It emphasizes the importance of staying open-minded and looking forward to new opportunities.