Usually a contract between the provider of the cloud computing  service and the customer is concluded. Here the duration, terms and extend of  the service is recorded. At this point problems can occur because the company  using the cloud computing service is now dependent on the provider. 

Obviously this dependency exists for the duration of  the contract but there can also be some technical constraints concerning  development tools that makes the customer dependent on the provider. Those development  tools are often offered by the provider to enable the customer to develop  custom cloud services. These tools often only work in the provided architecture  and thereby the custom services are tied to the provider. 

Due to the dependency on the provider a change of  contractor or switching back to in-house operation means that new cloud  services have to be developed matching the architecture of the new vendor. Also  the customer has to wait until the contract expires (BEISPIEL für wie lang). This  procedure can be very time consuming and costly and can lead to a  lock-in-effect. This means that a switch of the provider gets uneconomical due  to due to the high switch costs. 

Also the possibility that the provider could go broke  has to be mentioned. The customer does not know what will happen to the  servers, computer center and databases - including the own data. (Lissen 2014)