USA

Yes,
This is not a required criteria. But, it is definitely good to have a work experience. It shows maturity, skill, thought process, research mindset, amongst others. Needless to say, relevant work experience is better than irrelevant. But, some is better than none. Just work on remaining constraints.
Let's take a look at where each piece of the puzzle fits in. I will break it down into 2 categories:
Quantitative:
Aspects of your application that has numbers; that can be measured like your grades, GRE and TOEFL scores.Grades:
The higher, the better. But, it is not the end of the world, if you don't have a CGPA above 7.0 or 8.0. Why? Because of the other aspects of your application. GRE Again, the higher, the better. Beyond a certain score (330+), it doesn't really matter much; your amongst the best students. Now the other qualitative aspects of your application come into play. Below the universities minimum score, your application moves to the Stand-by pile.
TOEFL: Most international universities require it if your first language is not English. Some universities/graduation programs use a high verbal GRE verbal score as a substitute; do your research before taking the TOEFL. Meet the minimum criteria listed on their website and you'll be good. SOP: Some professors say this doesn't matter as much. Some professors read through them briefly, while some others place a greater emphasis on SOP.

Personnel management was basically concerned with recruitment, selection, placement of employees in organisations. Now the scope of personnel management has become wide and is concerned with organizing human resources with a view to maximize output and profits of the organisation and to develop the talent of the employees at work to the fullest possible extent securing personal satisfaction (job satisfaction of the employees) and personnel satisfaction (as far as the organisation is concerned). The scope of personnel management can be seen in terms of the activities of personnel management discussed hereunder: (a) Employee training (b) Recruitment and maintenance of labour force. (c) Executive development (d) Determination of equitable wages and Salaries for labourers and employees. (e) Job analysis and job description (f) Labour welfare activities-such as education to children of employee, recreation, sanitary conditions, etc. (g) Maintaining personnel records. (h) Maintaining sound human relations in industry. (I) Settlement of labour disputes.