Hi,
The default resource directory for all Maven projects is src/main/resources i.e. it will look for the WEB-INF/web.xml inside this location and as your web structure is not like this hence its throwing this error as its not been able to find the web.xml file. In order to override the location please use the plugin in your pom.xml as following assuming the WEB-INF/web.xml is located inside folder WebContent and pom.xml & folder WebContent are on same directory :-
<build>
<finalName>simple-webapp</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>2.1.1</version>
<configuration>
<webResources>
<resource>
<!-- this is relative to the pom.xml directory -->
<directory>WebContent</directory>
</resource>
</webResources>
</configuration>
</plugin>
</plugins>
</build>
This way you can create your WAR. Cheers!!!