I know that it's an extreme statement to make, but stay with me for a moment. I believe that Shonda’s emphasis of the carousel always turning is her way of showing that Meredith will cycle through life like her mother. Ultimately, for Meredith, this means she will end up getting Alzheimer’s.

1. Ellis wasn’t always cold.

We saw a young Ellis Grey in flashbacks of season 6. Although she was always intense, she was a young woman once too. She was passionate. She was clever. She was beautiful. She was a lot like Meredith was at her age. If Ellis Grey could transform over time into the cold, ruthless, surgeon she became later in life, so could her daughter.

2. The love of their lives (Derek and Richard) both left, one way or another

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Even though the circumstances between Derek and Richard leaving were different, the result was similar. Both Ellis and Meredith were left heartbroken and with at least one child to take care of on their own.

3. Ellis and Meredith left Seattle without a trace

As Richard stated in Season 11 Episode 22, aptly titled She's Leaving Home, "If she's gone, she's gone because she wants to be gone. She's doing what she knows how to do. Same as her mother." Meredith follows her mother's footsteps by leaving Seattle and staying almost completely out of contact with her previous life.

4. Meredith takes on her mother's demeanor as time goes by

Meredith has always been a little "dark and twisty" but in the later seasons, we see this more than ever. She seems generally unhappy, cold, and like her mother as the seasons reach 10 and 11.

5. The carousel never stops turning

Although the idea of the carousel came up first in Season 2 x Episode 5, Shonda Rhimes chose to bring it back as a major theme in Season 11. I believe that the carousel symbolizes cycles of life and the way in which Meredith cannot seem to avoid following in her mother's footsteps.

Whether or not Merdith gets Alzheimer's, lets to enjoy Grey's while it lasts. Because unlike carousels, this show won't last forever.