In my website, I am planning to show markers on the OSM map based on addresses. The user should have the ability to get directions to/from these markers. I noticed that the OSM is not able to locate addresses correctly and finding approximate addresses.
I am concerned about two things.
Whether the markers will be displayed on the map at correct location based on address
When the user puts his home address to get “Address to marker”, what if he gets a wrong location for his home address?
I also understand that Bing and Mapquest are based of OSM then how are they able to find all the addresses accurately?
This depends on what is present or not in OSM db. In some area, you just have a place name. In some, you have street names only. In some, you have addresses interpolation (house numbers ranges). In some, you have the full address for each building.
If you think that your area is not detailed enough about addresses details for your application, you can contribute or find people to add the addresses for you.
See how address can be added in OSM here: http://wiki.openstreetmap.org/wiki/Address