It is normal for all users to replicate your new system just the exact way your previous system was. SO this would mean you try to copy your old files as well. When I say old files, that can of course include the files of your programs as well. Now the trouble arises: you simply cannot do this and make your old programs run inn your new system. It us because they will require you to install them in the new system rather that just copying the files as such. This is not to say that there are exceptions for this. There are many games that will not want you to install them.
Now you have to know something about the need to install programs. The crux of the matter is that installing something is not that simple and it requires your computer to make use of diverse locations to copy the needed files. So this means considerable effort from the system and I should add that only when these conditions are met, will the program run efficiently. You can see that some of these actually make use of the Windows registry in order to save their matter and to identify these specific locations would be a tedious job from the part of any user.
Now the next thing that you have got to analyse is if you are actually eligible to reinstall these programs in any way easier? The answer to this very question is indeed complex and the first thing that you have to keep in mind is that always go for portable programs if they are good as well as these will make sure that you do not have to install them and this saves a lot of time as well. But make sure these are actually worthy.