buddherbhedam dhrityeshchaiva gunatastrividham shrunu |
prochyamaanamasheshena prithaktvena dhananjaya || 29 ||

According to gunaas, intellect and fortitude are said to be of three types also. Listen to this, completely and with its distinctions, O Dhananjaya.
buddhehe : intellect
bhedam : types
dhritehe : fortitude
cha : and
eva : also
gunataha : according to gunaas
trividham : three
shrunu : listen
prochyamaanam : are said
asheshena : completely
prithaktvena : with their distinctions
dhananjaya : O Dhananjaya
To recap the teaching so far, Shri Krishna provided a three fold classification of knowledge, action and the doer. Jnyaanam or knowledge prompts an individual to perform an action. The kartaa or doer is the state of mind while performing the action. Now, although the knowledge or jnyaanam aspect supplies the doer with the target of action, it does not prescribe a plan of action as to how to get that object. Therefore, the buddhi, the intellect, gives the course of action.
Once the intellect has determined the course of action, the doer needs to hold on to that course of action, and not arbitrarily get distracted or change its tactics. The quality of holding on to something in spite of obstacles is known as dhriti or fortitude. Shri Krishna says that intellect and fortitude are part of Prakriti’s gunaas. So they also are divided into three types. He proceeds to describe them in the next six shlokas. He also emphasizes that he will give a complete description, without leaving anything out.
So then, jnyaanam is the goal, buddhi is the plan and dhriti is adherence to the plan. Even in our daily life we see that different people can get the same outcome through different plans. And some people fail in face of obstacles, while some people persevere. Some people see a roadblock as an opportunity to think outside the box, whereas some people are completely flummoxed. Understanding how to plan and how to stick to the plan has benefits in the material path as well as the spiritual.