I'm re-posting this here as this question has come up before and I hope this answers why Fusion 360 is cloud based.
Fusion 360 was envisioned from the start as cloud based. Our team had worked on a desktop application called Inventor Fusion and we realized we wanted to build a ground breaking new 20-year vision. It was founded on connecting teams and design disciplines together in an integrated solution. There is much of that vision not available yet. It was a 20-year idea after all... but, there are real benefits that are there today. Most obvious is Fusion 360 desktop client data is available in the web and mobile clients and on other devices with versions that are managed automatically. This is already an advantage over desktop based tools.
There are other more subtly but important advantages. Rename for example. Renaming a SolidWorks part (without using special tools) will break any referencing assembly. Moving a SolidWorks part will break any referencing assembly. In Fusion 360 you can rename and move designs and any references will automatically know. In SolidWorks every assembly always opens the latest version of the parts you have on disk. Fusion 360 assembly references are version aware. This means when you roll back to an older version you will see that assembly exactly as that version was at that time in history including all of the child parts. Fusion 360 data can be shared with others using a public share. This share can allow others to self serve and download the file in the format they need. Fusion 360 data has a built in activity feed that lets you see versions and activity. This allows others to comment on designs and for this activity to be stored as part of a project keeping a history of changes and decisions. You get all this today without having to purchase EPDM, purchase Box/Dropbox or have a vault and data admin.
Using cloud technology as our platform helps ensure Fusion 360 is always the same version across the community so you can share data with other users and not worry about forward or backwards compatibility (Apple app store approval for Mac app store version can lag unfortunately). Fusion data is translated via cloud translation so that we are able to offer OS X users access to data that typically is not accessible on a MAC.
Other advantages over desktop tools is the ability for remote services to work on your data asynchronously as you work or sleep. Today renderings can be offloaded to be rendered using a cloud based compute grid for example.
Let's look at some of the benefits that we could deliver in the future that would not be possible with desktop based data. There will be additional clients that you can use to edit and create data. New clients like zero-browser clients and mobile clients that have access to your projects without any install. This will give you and your teams the ultimate flexibility to access and edit your data.
More services will be able to act on your benefit. Cloud grid computing will enable simulation studies, multi-variable design optimization and generative design tools. It will enable you to propagate change and have services update assemblies, drawings toolpaths and report on success or failure freeing designers to spend more time designing. It enables configurable parts to be deployed in engineer to order tools. It will enable 3rd parties to create new vertical solutions that can connect and enrich your projects no matter the device or your location.
Branch and merge of assemblies is built into the underlying data services for Fusion 360 and will allow individuals or teams to better manage change and explore design ideas. Branching and merging of design data is a nightmare to try and emulate on a desktop with folders and CAD file names. These are only some of the benefits that we think using the cloud as our platform will enable for you.
I think we have have been up front that Fusion 360 is cloud based. We do not promote it as a desktop design app and we would not want to mislead anyone that it is. I know that requests to make Fusion 360 a desktop app comes from an appreciation of how the design tool works and from a lack of appreciation of how the cloud service might benefit you. The benefit of cloud as a platform will take time to realize its' full potential. We are committed to take the time to listen to feedback from the community on that future direction and deliver on it, but, the feedback has to fit into the guardrails of the underlying product vision and values. Please don't misunderstand me. Resistance to ideas to "go desktop data" is not because of a disdain for you or ignorance of your desires. We have core values for what Fusion 360 can be and tying ourselves to the problems and solutions that were right for the last 20 years will constrain us trying to solve the challenges of the next 20 years.
I hope some of what we offer above and beyond desktop tools today is of value to you. I also hope what we will be able to offer in the future is of even more value to you. If it is not, then Fusion 360 might not be the right tool for you. That's O.K. We want to help people design and make their ideas real. There are other tools that might be a better fit and we can help point you in those directions. Now you may say that we could do all this on the desktop or that we should "Just do both." I hope some of the complexity of the capability above shows that this just has not been possible with local and file based data. Current tools have been trying to solve these problems for the last 20+ years and have not been able to do so. You might be able to get some of the above benefits with large very expensive and complex IT infrastructure but nowhere will you find all this available to hobbyist and students for free and to commercial customers for $40 to $100 per month.
I will add one more thought here. We know there are industries that don't allow the use of cloud data today. We are intentionally, and I hope honestly, acknowledge that, for now, Fusion 360 is not a fit for those users. There are so many great design tools and each of us just want to realize our ideas. You may not agree with Fusion 360's direction but that does not mean that is true for other users. If Fusion 360 is not a good, fit and there is anything we can do to help you find a tool this is a better fit for your needs, we are happy to help.
Kevin Schneider