A good web hosting service is one that provides effective technical support on a 24/seven basis. This is not only limited to hardware & software but also to other domain related issues such as integration with payment gateways, procurement of SSL certificates, advice on newsletter software or RSS feeds.
Unfortunately such web hosting services are very few in number. Most only make tall claims but don't invest enough on equipment and competent support staff. Some are not even hosting companies but mere resellers. Still they make big promises. It is for the webmaster to choose the right web host.
The web master must make a sincere effort to find out the competence of the technical and support staff employed by a web host. It is this staff that you will have to call, if anything goes wrong with your web site.
Hosting services often boast of providing technical back-up 24 hours a day in their operation centers. However, the reality is that most of them struggle to locate staff trained in operating systems and network technology. Some companies spend more on advertising and marketing than on customer support.
That is why you need to call up customer support and enquire about their basic maintenance routines, availability, professional training, certification, years of experience, years of working with the service provider, etc. Try to judge their level of expertise by asking pointed, technical questions about their skills as well as the hardware and software deployed in their premises.
Ask the support staff where they are located and where the office of the hosting service provider is. You can also directly ask if the staff is employed by the host or is working on a contractual basis. This will help you to find out if the customer support services have been outsourced. If the customer support technicians put you on hold very often, this may indicate that they are there only to convey service requests to others.
A hosting service may provide you with hard copy of its technical back-up documentation. It may also allow you to download a PDF file with all the relevant details presented in a highly professional style. But don't be misled by such documents. Do your own research before signing on the dotted line. Without good technical support you are sunk.