1. It is made to measure to the exact requirements of your enterprise so you don't compromise on any feature you require and that will fulfill your needs in full.
2. It is an elegant long-standing investment. Custom software development is certainly an expensive option because you have to start from scratch based on your custom requirements but it is an elegant investment in the long run. Ready software has lots of features that you do not need and might never use them and additional hardware might be required to operate. You can also get rid of copy rights, renewals and license issues when you go with custom software solutions for your enterprise. It will also be easy for your team to use it efficiently.
3. Your software maintenance and up gradation will be in your control and this is the big thing to be consider to go with custom software instead of off-the-shelf ready software. If you go with ready solutions you are on the mercy of the development company and your business is in vulnerable position always. They upgrade the software the way they think and you have to buy upgrades again with lots of unnecessary features. You also have to pay the renewals and you still have risk if anything goes wrong because the development company mostly own all the rights.
4. Software security is another challenge you must think, the custom software is more secure than ready software. Ready software is available to everyone so there are open vulnerabilities and there are more chances to be hacked but in custom software it will be a relation of you with the development company so there are no open vulnerabilities and less chances of hack.
5. Scalability of the software is very important point to be considered. When you choose custom solution the software is developed by considering your further requirements so you can add more features easily if your business grows but in ready software you might be helpless and at that time you will have option to switch to custom solutions.
6. Who will provide you the after sales support is really another important point to be considered. In custom software case you will most probably get support from the team developed it quickly and economically but in ready solutions you will get support from ordinary support team.