Table:
|  |  | Year Ended December 31, |  |
| --- | --- | --- | --- |
|  | 2019 | 2018 | 2017 |
| Warranty reserve, beginning of period | $8,220 | $8,306 | $2,158 |
| Provisions made to warranty reserve during the period | 13,708 | 11,775 | 16,597 |
| Charges against warranty reserve during the period | (11,574) | (11,861) | (10,449) |
| Warranty reserve end of period | $10,354 | 8,220 | 8,306 |
Paragraphs:
COMMITMENTS AND CONTINGENCIES
Warranties
The Company’s standard warranty obligation to its customers provides for repair or replacement of a defective product at the Company’s discretion for a period of time following purchase, generally between 12 and 24 months. Factors that affect the warranty obligation include product failure rates, material usage and service delivery costs incurred in correcting product failures. In addition, from time to time, specific warranty accruals may be made if unforeseen technical problems arise. The estimated cost associated with fulfilling the Company’s warranty obligation to customers is recorded in cost of revenue.
Changes in the Company’s warranty liability, which is included as a component of accrued liabilities on the consolidated balance sheets, are set forth in the table below (in thousands):
Question:
What are 3 factors that can affect warranty obligation?