It will never look like that. It is all too easy to fall into the trap of investing large amounts of time in a design and being confident that the implementation will come out the same. A detailed design can easily fool you into believing you have every angle covered. The greater the detail and the more in-depth the research the greater your confidence in it. But it is an illusion: it will never look like that.
The truth is no matter how in-depth, how well researched and how well thought out your design it will never come out looking the same as in your head. Something will happen, an external factor may effect the design: incorrect information, a limitation, an odd behaviour in someone else’s code. Or you may have got something wrong: an oversight, an incorrect presumption, a subtle concept missed. Or something will change; the requirements, the technology, or someone may just find a better way(TM).
Those minor alterations in the design soon stack up and lots of minor alterations soon require that one big one has to be made. Before long your original concept is on the floor in pieces and its back to the drawing board. You decide what you needed was more design, more detail, so back you go and the next architectural vision is clearer, more radical, more perfect than the last. But before long the same thing happens, those changes start to appear and shift your design and developers keep shoving in more and more stuff trying their best to work around the broken design but just breaking it more and you end up screaming “of course it’s got bugs; it was never designed to do that!”.
Design is a discovery process, as we implement we discover new information, often impossible to know up front. By accepting that design is an ongoing and empirical process in a forever changing world, we learn that the design process must be flexible and ongoing too. Clinging onto your original designs and trying to force them through is only going to end up with one result so you need to learn to understand that it will never look like that.