Many of you may know about how you can squint your eyes to make the images more clearer. Can someone explain why some of these images get a lot more realistic -

Many of you may know about how you can squint your eyes to make the images more clearer. Can someone explain why some of these images get a lot more realistic - e.g. the lion [1], the girl [2]..while there is not much improvement for the others - e.g. the barn[3], the small aircraft [4] (or at least that is what I think it is)? [1] https://camo.githubusercontent.com/0cb3ad89ff63a7fcca22e1f20b941eb74d44894e/68747470733a2f2f7777772e6d69636861656c666f676c656d616e2e636f6d2f7374617469632f7072696d69746976652f6578616d706c65732f31353139393233373039352e3230302e3132382e342e312e706e67 https://camo.githubusercontent.com/0cb3ad89ff63a7fcca22e1f20... [2] https://camo.githubusercontent.com/37d464fc15376c548a1ecf37aaa230b9a1a2c550/68747470733a2f2f7777772e6d69636861656c666f676c656d616e2e636f6d2f7374617469632f7072696d69746976652f6578616d706c65732f31313730373831393736342e3230302e3132382e342e312e706e67 https://camo.githubusercontent.com/37d464fc15376c548a1ecf37a... [3]https://camo.githubusercontent.com/95f92b2505523e8f23f733bb025bc4ef7f6df2ad/68747470733a2f2f7777772e6d69636861656c666f676c656d616e2e636f6d2f7374617469632f7072696d69746976652f6578616d706c65732f31353031313736383730392e3230302e3132382e342e312e706e67 https://camo.githubusercontent.com/95f92b2505523e8f23f733bb0... [4] https://camo.githubusercontent.com/5cc4416030a43025d6861b3e6541bfacd5e4ba77/68747470733a2f2f7777772e6d69636861656c666f676c656d616e2e636f6d2f7374617469632f7072696d69746976652f6578616d706c65732f31353031353431313837302e3230302e3132382e342e332e706e67 https://camo.githubusercontent.com/5cc4416030a43025d6861b3e6...