heroku apps not running forever script.js

Question

I have a heroku app created on my local system and pushed it to heroku then i ran

heroku run node_modules/forever/bin/forever start server.js

and i got this response -

warn:    --minUptime not set. Defaulting to: 1000ms
warn:    --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms
info:    Forever processing file: server.js

and after that if i run

heroku run node_modules/forever/bin/forever list

I got -

Running `node_modules/forever/bin/forever list` attached to terminal... up, run.5132
info:    No forever processes running

and the heroku logs here have -

Starting process with command `node_modules/forever/bin/forever start server.js` by harshitladdha93@gmail.com
2014-07-05T17:24:54.833343+00:00 heroku[run.5098]: State changed from starting to up
2014-07-05T17:24:58.695683+00:00 heroku[run.5098]: State changed from up to complete
2014-07-05T17:24:58.689043+00:00 heroku[run.5098]: Process exited with status 0

this, and my server.js has -

var async = require('async');
var shell = require('shelljs');

async.parallel([
        async.apply(shell.exec, './collect1.sh'),
        async.apply(shell.exec, './collect2.sh'),
        async.apply(shell.exec, './collect3.sh'),
        async.apply(shell.exec, './collect4.sh'),
        async.apply(shell.exec, './collect5.sh'),
        async.apply(shell.exec, './mi2.sh'),
    ],
    function (err, results) {
        console.log(results);
    });

and these shell scripts are long executing files with huge amount of delays but the logs say that the state from up to complete, but I don't understand why as in my local system it creates more processes and sleep states and it runs fine so, heroku doesn't allow this or I am making some mistake here.