Open Source is the only solution guaranteeing non-dependence on a software vendor. This is commonly called "Vendor Lock-in". Using open source, you protect yourself against the following risks :
- Takeover of the software vendor and therefore licence policy changes
- Evolution of prices
- Degradation of the relationship with the software vendor
- Changes to the standards of use (hosting conditions, non-support for certain integrations)
- Changes to security standards or hidden backdoors