Hello Jam£s,
It sounds like you are closing the Safari window with the red close button before you quit Safari. When Safari is quit and reopened it opens the windows that were active (open) when it was quit.
Automatically re-open windows, apps, and documents on your Mac - Apple-kundestøtte
For example, when you quit Safari, any webpages you're viewing are fully restored the next time you open Safari.
By closing the window before you quit Safari you are telling Safari not to automatically open it on relaunch. Leave the windows open instead when you quit Safari.
Note there are other ways to get to previously opened sites.
Safari 8 (Yosemite): Revisit webpages
- See pages you visited in this window or tab: Click the Back button
or Forward button
in the toolbar. If you have a trackpad or mouse that supports gestures, swipe left or right to move through your history
-
Choose from a list of previous pages:
Press and hold the Back button or Forward button.
-
Choose from a longer list of webpages you’ve visited:
Choose a webpage from the History menu, or choose Reopen Last Closed Window or Reopen All Windows from Last Session.
-
View all the webpages in your browsing history:
Choose History > Show History.
-
Visually browse thumbnails of webpages you visit frequently:
Choose History > Show Top Sites.
-
Visit pages on your Reading List:
Click the Sidebar button
in the toolbar, then click Reading List.
Best,
Nubz