Where that number come from? Why?
If you read the article on the link, you will find the answer to that question. Here is the reason the logo maker tilted it to a certain degree:
Why rotate the B shape by 14° on the logo ?
14° came about by adding an infinite number of B’s together by dividing the previous value by 10.
12.5 + 1.25 + 0.125 + 0.0125 + 0.00125 + 0.000125 + 0.0000125 + 0.00000125 + 0.000000125 + 0.0000000125 + 0.00000000125 + 0.000000000125 …
This comes to about 13.888 repeating.
When using a drawing program that rounds the rotation angle to the closest full percent, the angle becomes 14°.
The angle represents the blockchain progressing into the future forever.
You can also read about this Bitcoin Logo at Bitcoinmagazine.com. Here's another explanation of why Logo B tilted to that degree:
For example, the number eight pops up multiple times in the dimensions and geometry of Bitcoin’s design (e.g., the B is rotated clockwise 13.88 degrees — more on this later). Per the internet language 1337, an eight resembles a B, which is short for “Block,” according to Wilson. Many of the patterns that went into creating the Bitcoin logo’s design, like the circles that eventually made up the B, contain the number eight. The dimensions of other shapes (like the rectangles in the design) had a length of 12.5 (or, one-eighth of 100, thus representing eight yet again).
Since eight is B, which stands for block in this symbology, each new pattern is like adding a new block to the logo. Everytime a shape is resized (as they were multiple times throughout the design process) this reflects the changing data size of each new block.