All you need is time!When you are on your own, your biggest constraint is time. You may have 100 ideas, but the day has 24 hours and you will need all of them to create something big. So setting up something like a git server is just a waste of time if you can get one for almost no money. First, you need time for the setup. Then, you need time to maintain it. Your server may go down, you may have a crash and the need to set it up one more time. You may encounter some flaw in your setup which you need to fix - And there goes half a day. And the worst part is that you end up with something not even close to github or bitbucket. Gitosis is ok, but the web interface of both is great and all the tools you have are very good!
And setting up a bitbucket account and some private repositories is so plain simple. It took me 10 minutes and now I have 3 repositories with a nice gui on top. I don't care about maintainance or server issues. I can add issue tracking or a wiki for every repository. I can add collaborators, can manage permissions and many things more.
The same is true for other software as well. Take Google Apps: For $5 a month/user you get email, google drive/docs, google sites, google talk and much more with a nice interface. Setting up your own email server infrastructure seems such a waste if you are a small startup, knowing nothing about email and without special needs.
Just let someone take care of it, pay them their fair share and everybody wins.
Doesn't anybody think about the data?Many people will turn down every attemt to outsource with the data security argument. While this should be an issue and you might not want to host your git repositories on a unknown page named wehostyourgitrepositoriesforfree.cc, the argument is not as strong as many people think.
Do you really think the code is secure on your servers? Do you have security experts working for you, securing your network? Would you even recognize someone looking at your git repositories? Would you be able to spot someone downloading all the emails from your mail server? Do you really think you can set up a more secure infrastructure than Google or Github? I don't know, but I highly doubt it.
And there is another issue: Do you really need that much security? Of course, if security would come for free (which it does not!), then the more the better. But security has it's price, and you are not willing to pay it if you just set up your server and hope it's secure.If you are serious, hire a security expert. Too expensive? There we go...
The "real" drawbacksAre there drawbacks? Well, if you are willing to spend thousands of dollars to migrate from one piece of software to another. If you are willing to invest serious money in developing a plugin for the feature you are missing. In this cases there is the drawback that this might not be possible with SaaS-Software. You cannot just migrate, because the data is not on your server. There might be some sort of export or there may not. If you really think this could be an issue, check the solution you want to use if they have an export. At mite for example, which I use for time tracking, there is a export of all my data, which means I can migrate everytime.
If you don't plan on migrating and don't expect to extend the software, you could bring money up. Calculate $22/month for 20 private github repositories or $50/month for 10 google app accounts for some years and you end with serious money. You could save yourself a bit if you do it yourself. But count all the maintainance, server upgrades, backups and so on and more often than not you end with way more than those $50.
One argument I hear often is that when using a SaaS provider, you rely on them. Which, of course, is true. But that's how it works and it's nothing new. You do it everyday and don't even think about it. You rely on power, water, heating. ou rely on your internet connection, telephone cable. You rely on public transportation to get your employees to work. You rely on the government to be stable so laws don't change everyday. If you start doing all of this on your own, you don't have any time left to do real business. Using SaaS is just the next step.