I used to spend about two months putting a character together. I'd spend weeks assembling a mod list, creating a look for the character, making custom weapons, armor, jewelry, clothes, ect and, finally, making a custom house for the character to live in. All the while, the personality and history of the character would be forming in my mind. By the time I was ready to start a game, I would know almost everything about the character: how they spoke, how they moved, childhood memories, their hopes and fears, what side of the bed they slept on and what their favorite color was. I knew exactly which quests the characters would be doing and how the character would do those quests.
That changed with Skyrim. I think Skyrim encourages a more non-traditional approach to roleplaying. The fact that characters begin a game more or less on an equal footing encourages a discover-as-you-play approach to developing a character. So these days I'm more likely to start with a rough idea of who my character is what is is likely to do in the game, and improvise. I am actually finding this to be a great deal of fun. My roleplaying these days feels more exploratory, surprising. My characters are more likely to change in response to events they experience. I never quite know where a game is going to end now, no matter where a game begins.