This should be the most common impact to company where more manpower usually will lead to better productivity. In some cases, manpower also the important factor in deciding whether the project can be done in time or efficiently. If the project is too huge and company does not have enough manpower to handle it, then company may force to give up on the project in order to avoid situation where company situation may have ruined if the accepted cannot be done.
Maybe some of you cannot related lack of manpower to safety. However, company that does not have sufficient manpower will have threat on safety of employee. If a company does not have sufficient manpower, then the workload for employee will increased. As the workload increased, employee will need to finish their huge workload with limited amount of time and this may make their very stressful and even burnout.
Option and Innovation
When company is lack of manpower, they will have more option on hiring employee and they can use this chance to hired high quality of employee for their company. Other than that, employee shift also can be switch easily. Sometimes employee may want to switch their work shift with other employee for some emergency situation. If company lack of manpower, they can switch easily where they no need to get through multiple process to get permission to switch their work shift.
Employee are not just having improvement with their employer but with their colleague as well. If company have sufficient manpower in the company, employee can share their knowledge with others and employers may no need to put much time on guiding them. If company does not have sufficient employee, then it may be much difficult for employee to develop themselves where they just can learn from their employer and difficult to get other knowledge other than from their employer.