Well I recently got hold of a Unity model pack where a single building was over 200k in size… making a single street resulted in over 2 million polygons in the stats screen and i hadn’t even added people or props yet…
Then I tried to create the pavements using the included sections and found that the only corner piece had a hole cut into it for use with a unique corner building that came with the model. This meant having to take the purchased models into Maya and modifying it before it could be of any use.
So I go in and i find that this pavement has polygons facing the ground and towards the buildings… I was disgusted in the amount of wasted polygons. When I buy something I expect value for money… but when you create a gutter and use 50 polygons simply because you have 9 divisions right in the middle and do nothing with the polygons, then I feel cheated…
When I buy something I hate having to fix it before I use it and my modeling courses always taught to inspect my models on a polygon by polygon basis and deform each limb one at a time, swopping edges on a polygon by polygon basis until everything looks just right… Delete everything that will never be seen and make sure what is there, works.
When I buy a wall and find it has polygons facing the ground I consider the modeler as a thief. He promised me a wall and gave me a plain, simple cube with a texture applied. If I wanted to buy a texture I would have bought a texture pack. When I buy a model I expect it to have been modeled…
What constitutes “professional”, in relation to the training I received has made me very skeptical about buying anything ever again. What constitutes “professional”, from what I have seen, means making it myself is a better option…
What I would suggest is this: Look at your model. See if a polygon will EVER be seen or not. If not, ever, under any circumstances, then get rid of it… But inspect your model very carefully…
For instance: Say you build a wall piece with a unique top. if I decide to use that model upside down as a fancy roof decoration, will it work? If it will work as an upside down model then obviously you can not delete the top.
If on the other hand, your model looks like logs tied together with rope and cut to sharp ends on the top and bottom… If you built it as a model then the piece could be used as a vertical moving hindrance so there the top and bottom will be seen and must be included, but if you only stuck a texture onto a cube then looking at the bottom at an angle will just suck so just delete the bottom and force your customers to always use the wall as you intended.
This question you asked, I believe, should be evaluated on a per-model basis to evaluate what is best for the particular model and not used as a “Well I was told to do this so I can build the model this way to fit in with the predetermined answer I got to that question from someone that time”
A wall piece should not HAVE to have a corner piece to make it complete. It should be used with or without it as your CUSTOMER sees fit. Based on that, decide wether a face should be there or not… but for Pete’s sake, if you are gonna charge people money for supposed “work” you have done, don’t build them a pavement with polygons that face down… Nobody will ever, under any circumstances look at a pavement from underneath…