Usually the impetus that moves the ‘‘progressive discipline’’ process
from one stage to the next is a repeated violation of the same rule
or type of rule (e.g., repeated absenteeism or substandard job performance). In essence, there must be a link or nexus between events in order to move to the next stage. Without an interrelationship between events, you may end up with a series of first-level warnings (sometimes called verbal warnings), rather than a progression from a verbal to a written to a finalwritten warning.

Tell Me More
Let’s assume that a one-year benefits clerk is having difficulty staying on top of her work, following up with customers, and collecting outstanding receivables. The individual was verbally counseled one month ago and instructed to work more efficiently, to keep her boss informed of her progress, to ask for help when she was falling behind, and to minimize any further occurrences of excessive personal telephone calls and extended breaks.

Since that time, the person continued to fail to meet these ex
pectations and received a written warning (see Appendix L for sample written warnings). About five weeks later, the employee
improved her conduct by avoiding any further occurrences of extended breaks or personal phone calls; however, a major error occurred with a large account. This became grounds for a final written warning. (See Appendix L for a sample final written warning.)

Any subsequent performance or conduct violations within a
reasonable period of time from this point would probably result in
a termination for cause.

Taken From : The Hiring and Firing Quention and Answer Book