I saw a doctor who diagnosed varicose veins. Now he wants to do treatment. I suspect he is churning. What is significance of the condition?

Get a second opinion. Varicose veins often cause pain, heaviness, cramping, and restless legs syndrome. They can also cause swelling, discolored skin, bleeding, blood clots, and ulcers. If you have varicose veins and any of these, it is worth considering having treatment done. If you have seen a doctor about your veins and you aren't sure about what you are being told, getting a second is always a good idea.
Tx may be indicated. Indications for treatment of varicose veins include cosmetic concern, symptoms caused by varicose veins (leg pain, heaviness, others), complications caused by veins (swelling, eczema, ulceration), and prevention of worsening of the veins. While varicose veins are generally are not life threatening they do, in most cases, get worse gradually over time, and significantly reduce the quality of life.
Agree to treat VV. Presence of vv is manifestation of underlying venous valve incompetence. Evaluation with ultrasound of the venous system in the legs is indicated, and seeking treatment by a phlebologist (specialist in venous disease) should give you satisfactory results. Do not understand "churning.".
Varicose veins. Varicose veins can cause minor or major problems & it is always a good idea to get them evaluated by a board-certified vascular surgeon for recommendations.Sometimes it is appropriate to manage them conservatively with compression stockings & other times interventional therapy is best. If you have venous reflux, it can cause pain, swelling, skin damage, blood clots, or even ulcers with progression.
Veins worsen. I did not understand "churning"? Look up american college of phlebology website to start to understand this disease and www.Morrisonvein.Org varicose veins can lead to deep vein thrombosis called DVT or at the least cause skin changes, cramping, restless legs, swelling, or leg ulcers or vein ruptures. It is better to get treated early now that there are minimally invasive procedures.
They may need it. Varicose veins warrant treatment when they are causing pain, swelling, or skin changes. New treatment options such as ablation and sclerotherapy are much better tolerated than stripping and phlebectomy. You can learn more at web sites like phlebology.Org or healthyveins.Com. Treatment web sites like vnus describe varicose veins as well, but are more specific in descriptions of treatments.